JP2606445B2 - Linear actuator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear actuator for moving an optical head in an information recording / reproducing apparatus for recording or reproducing information on an optical disk.

2. Description of the Related Art In recent years, optical disk memories have attracted attention as high-density, large-capacity memories, and research and development of small, thin, and high-speed information recording / reproducing apparatuses using optical disk memories as information recording media have been actively conducted. .

Hereinafter, an example of a conventional linear actuator used in an information recording / reproducing apparatus will be described with reference to the drawings.

FIG. 7 is a perspective view showing the appearance of a conventional linear actuator, and FIG. 8 is a configuration diagram showing a support configuration of the conventional linear actuator.

7 and 8, reference numeral 1 denotes a disk cartridge, 2 denotes an optical head, 3 denotes a moving section on which the optical head 2 is mounted, 4 denotes a moving direction of the moving section, and 5 denotes a moving direction parallel to the moving direction 4. A pair of guide shafts 6 are fixed to the moving unit 3 and support the moving unit 3 with respect to the guide shaft 5 and reciprocate in the moving direction 4. 9 presses the rotating member 6 against the guide shaft 5. A driving coil having one end fixed to the moving unit 3 and the other end supporting the rotating member 6; a driving coil 7 fixed to the moving unit 3 and having a winding center axis arranged parallel to the moving direction 4; Reference numeral 8 denotes a magnetic circuit that generates a magnetomotive force in a direction perpendicular to the winding center axis of the drive coil 7.

The operation of the conventional linear actuator configured as described above will be described below with reference to FIGS. 7 and 8.

First, a voltage is applied to both terminals of the drive coil 7 by a drive circuit (not shown), and a current flows through the drive coil 7. A magnetic flux perpendicular to the direction of the current flowing through the drive coil 7 is generated by the magnetic circuit 8, and the moving direction 4
Electromagnetic force is generated. As a result, the electromagnetic force received by the drive coil 7 is transmitted to the moving unit 3, so that the moving unit 3 supported on the guide shaft 5 via the rotating member 6 moves in the moving direction 4.

However, in the above-described configuration, since the rotating member 6 must be arranged at a predetermined angle up and down with respect to the two guide shafts 5, the height of the supporting mechanism is reduced. There is a problem that it is difficult to reduce the thickness of the linear actuator because it becomes large.

Further, since the thinning of the apparatus and the speed of the seek are required, when the magnetic circuit 8 and the drive coil 7 are configured in a small space below the disk cartridge 1, there is a problem that the thrust of the linear actuator is insufficient. Was.

The present invention has been made in view of the above-mentioned problems, and has a configuration in which the use of four guide shafts or guide plates makes it possible to reduce the thickness of the support portion, and further, does not provide a magnetic circuit and a drive coil in the space below the disk cartridge. It is intended to provide a linear actuator which is thinner and can achieve high thrust.

Means for Solving the Problems In order to solve the above problems, the linear actuator of the present invention comprises a disk cartridge and a moving part that linearly reciprocates a predetermined distance below the disk cartridge and reciprocates below the disk cartridge. A first pair of guide shafts arranged in parallel with the movement direction and symmetrically with respect to the moving portion;
A second pair of guide shafts arranged symmetrically with respect to the moving unit below or above the first pair of guide shafts below the disk cartridge, and on a plane perpendicular to the direction of the reciprocating motion of the moving unit; At least three first shafts mounted on a moving unit having a rotating shaft and restricting the support of the substantially vertical moving unit facing the disk cartridge by rotatingly contacting the first pair of guide shafts. A moving member that has a rotating shaft on the same plane as the rotating member, and restricts the support of the moving portion in a substantially horizontal direction orthogonal to the substantially vertical direction by rotating and abutting on a second pair of guide shafts. At least three second rotating members mounted on the moving part and at least one rotating member of the second rotating member which is mounted on the moving unit at a predetermined pressure to press the second pair of guide shafts And the direction of reciprocation outside the moving part And a magnetic circuit which is symmetrically disposed, and the driving coil fixed to both sides of the moving portion to obtain a driving force in the direction of the reciprocating motion by a magnetic field generated in the magnetic circuit with respect to the parallel and mobile unit.

Also, a moving portion linearly reciprocating a predetermined distance below the disk cartridge and the disk cartridge, and a first pair of guides arranged below the disk cartridge in parallel with the reciprocating direction and symmetrically with respect to the moving portion. A second shaft disposed symmetrically with respect to the moving part on the inside and outside of the first pair of guide shafts below the disk cartridge;
A pair of guide shafts, and a rotation shaft on a plane perpendicular to the direction of the reciprocating motion of the moving unit, and a rotating shaft in contact with the first pair of guide shafts while rotating in a substantially vertical direction facing the disk cartridge. A rotating shaft is provided on the same plane as at least three first rotating members mounted on the moving unit that regulates the support of the moving unit. The rotating shaft is in contact with the second pair of guide shafts while rotating. At least three second mounts mounted on the moving unit that controls the support of the moving unit in a substantially horizontal direction orthogonal to the substantially vertical direction
A rotating member, a pressurizing unit mounted on the moving unit, and pressing at least one rotating member of the second rotating member with a predetermined pressure to abut against a second pair of guide shafts; A magnetic circuit arranged outside the cartridge and behind the disk cartridge in parallel with the direction of reciprocating motion and symmetrically with respect to the moving portion, and a rear portion of the moving portion which obtains a driving force in the direction of reciprocating motion by a magnetic field generated in the magnetic circuit. And a drive coil fixed to the drive coil.

Further, the moving part linearly reciprocating a predetermined distance below the disk cartridge and the disk cartridge and the moving part below the disk cartridge in parallel with the reciprocating direction and symmetrically with respect to the moving part, A pair of guide plates in which the cross-sectional shape of the orthogonal plane is substantially V-shaped, and two substantially V-shaped convex side surfaces or two concave side surfaces are arranged to face the cartridge;
One of the concave side surfaces of each of the pair of guide plates
A pair of guide plate surfaces, a second pair of guide plate surfaces each including one of the convex side surfaces of each of the pair of guide plates, and a direction of reciprocating motion of the moving unit. A rotating shaft on a vertical plane, supporting a moving portion in a substantially vertical direction or a substantially horizontal direction orthogonal to the vertical direction facing the disk cartridge by rotating and abutting on the first pair of guide plate surfaces. A rotating shaft on the same plane as at least three first rotating members mounted on the moving unit that performs the regulation, and a substantially vertical direction by rotating and abutting on a second pair of guide plate surfaces; Alternatively, at least three second rotating members mounted on the moving unit that controls the support of the substantially horizontal moving unit, and at least one of the first rotating member or the second rotating member mounted on the moving unit. Rotating members A pressurizing means to abut the guide plate surface of the guide plate surface or the second pair of the first pair and pressed at a constant pressure, outside of the disk cartridge,
And a magnetic circuit parallel to the reciprocating direction behind the disk cartridge and symmetrically arranged with respect to the moving portion, and a drive coil fixed to the rear portion of the moving portion that obtains a driving force in the reciprocating direction by a magnetic field generated in the magnetic circuit. Configuration In addition, the guide plate has a substantially V-shaped cross section in a plane perpendicular to the reciprocating direction.
One piece having a shape in which two substantially V-shaped convex side surfaces or two concave side surfaces are opposed to the cartridge and a pair of substantially V-shaped ends are connected to each other. It consists of a sheet metal.

Action The present invention reduces the arrangement of the rotating member to 2 by the configuration described above.
By dispersing to the pair of guide shafts, a support system of the moving unit can be configured within a height of the sum of the diameter of the rotating member and the diameter of the guide shaft, and a plate having both ends folded into a V shape By using the shaped member as the guide plate, further reduction in thickness can be realized and low cost can be achieved. In addition, by eliminating the magnetic circuit and the drive circuit from the space below the disk cartridge and arranging them behind the disk cartridge, a low-cost, thin, high-thrust linear actuator can be realized.

Embodiment Hereinafter, a linear actuator according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an appearance of a linear actuator according to a first embodiment of the present invention, and FIG. 2 is a configuration diagram showing a support configuration of the linear actuator according to the first embodiment of the present invention.

In FIGS. 1 and 2, 1 is a disk cartridge, 2 is an optical head, 3 is a moving part that moves linearly a predetermined distance below the disk cartridge, 4 is a moving direction of the moving part 3, and 5 is a moving direction. 2 which is arranged below the disk cartridge 2 in parallel with the moving direction 4 and symmetrically with respect to the moving portion 3.
A pair of guide shafts 6, at least one of which is in contact with each guide shaft 5, and a plurality of rotating members mounted on the moving unit 3 having a rotation axis in a direction perpendicular to the longitudinal direction of the guide shaft 5, 9 2
A pressurizing spring that presses against any three of the pair of guide shafts 5 with a predetermined pressure and presses against the rotating member 6. The pressurizing spring 8 is arranged outside the moving unit 3 in parallel with the moving direction 4 and symmetrically with respect to the moving unit 3. And a driving coil 7 fixed to both side surfaces of the moving unit 3 that obtains a driving force in the moving direction 4 by a magnetic field generated in the magnetic circuit 8.

The operation of the linear actuator configured as described above will be described below with reference to FIGS.

First, a voltage is applied to both terminals of the drive coil 7 by a drive circuit (not shown), and a current flows through the drive coil 7. A magnetic flux perpendicular to the direction of the current flowing through the drive coil 7 is generated by the magnetic circuit 8, and the moving direction 4
Electromagnetic force is generated. As a result, the electromagnetic force received by the drive coil 7 is transmitted to the moving unit 3, so that the moving unit 3 supported on the guide shaft 5 via the rotating member 6 moves in the moving direction 4.

As described above, according to the first embodiment of the present invention, by providing two pairs of guide shafts 5 (four shafts as shown in the drawing) in the space below the disk cartridge 1, the rotating member 6 is provided.
Can be arranged in a plane, and the supporting portion can be formed within a height of the sum of the diameter of the rotating member 6 and the diameter of the guide shaft 5, and the lower portion of the disk cartridge 1 including the magnetic circuit 8 and the drive coil 7 can be formed. A thin linear actuator can be realized in a space, and operationally equivalent characteristics to those of the conventional example can be obtained.

Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a perspective view showing an appearance of a linear actuator according to a second embodiment of the present invention, and FIG. 4 is a configuration diagram showing a support configuration of the linear actuator according to the second embodiment of the present invention.

3 and 4, reference numeral 1 denotes a disk cartridge, 2 denotes an optical head, 3 denotes a moving unit which moves linearly a predetermined distance below the disk cartridge, 4 denotes a moving direction of the moving unit 3, and 5 denotes a moving direction of the moving unit 3. 2 which is arranged below the disk cartridge 2 in parallel with the moving direction 4 and symmetrically with respect to the moving portion 3.
A pair of guide shafts 6, at least one of which is in contact with each guide shaft 5, and a plurality of rotating members mounted on the moving unit 3 having a rotation axis in a direction perpendicular to the longitudinal direction of the guide shaft 5, 9 2
A pressurizing spring 8 presses any three of the pair of guide shafts 5 with a predetermined pressure to press the rotating member 6, and a pressurizing spring 8 is provided outside the disk cartridge 1 and behind the disk cartridge 1 in parallel with the moving direction 4. The magnetic circuit 7 symmetrically disposed with respect to the moving unit 3 includes a drive coil fixed to the rear of the moving unit 3 that obtains a driving force in the moving direction 4 by a magnetic field generated in the magnetic circuit 8.

 The operation is performed in the same procedure as in the conventional example.

As described above, according to the second embodiment of the present invention, by providing two pairs of guide shafts 5 (four shafts as shown in the drawing) in the space below the disk cartridge 1, the rotating members 6 are dispersed in a plane. It is possible to arrange the support portion within a height obtained by adding the diameter of the rotating member 6 and the diameter of the guide shaft 5,
By reducing the thickness of the linear actuator support portion, the magnetic circuit 8 and the drive coil 7 can be arranged behind the disk cartridge 1 having a relatively large space in which the height of the support portion and the thickness of the disk cartridge 1 are added.
A thin, highly efficient linear actuator that generates high thrust can be realized.

Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

FIG. 5 is a perspective view showing an appearance of a linear actuator according to a third embodiment of the present invention, and FIG. 6 is a configuration diagram showing a support configuration of the linear actuator according to the third embodiment of the present invention.

5 and 6, reference numeral 1 denotes a disk cartridge, 2 denotes an optical head, 3 denotes a moving unit which moves linearly a predetermined distance below the disk cartridge, 4 denotes a moving direction of the moving unit 3, and 10 denotes a moving direction. A portion having a V-shaped cross section below or above the disk cartridge 1 and a V-shaped opening disposed above or below the disk cartridge 1 is arranged in parallel with the moving direction 4 and symmetrically with respect to the moving portion 3. A guide plate 6 having one end connected to the lower side of the moving unit 3, at least one of which is in contact with one of a V-shaped concave surface and one of a convex surface, and a pair of guide plates 10. A plurality of rotating members 9 mounted on both side surfaces of the moving part 3 having a rotating axis in a direction perpendicular to the longitudinal direction of the moving member 3 are fixed to any three surfaces of a pair of guide plates 10 with which the rotating member 6 contacts. Pressurizing bar which presses the rotary member 6 by pressing , 8 are magnetic circuits arranged outside the disk cartridge 1 and behind the disk cartridge 1 and parallel to the moving direction 4 and symmetrically arranged with respect to the moving section 3, and 7 is driven in the moving direction 4 by a magnetic field generated in the magnetic circuit 8. And a drive coil fixed to the rear of the moving unit 3 for obtaining a force.

 The operation is performed in the same procedure as in the conventional example.

As described above, according to the third embodiment of the present invention, one guide plate 10 having a V-shaped cross section at both ends is provided below the moving unit 3 in the space below the disk cartridge 1. Accordingly, the rotating members 6 can be dispersedly arranged in a plane, and the supporting portion can be formed in an extremely thin space in which the diameter of the rotating member 6 and the thickness of the guide plate 10 are added. And cost reduction, and the magnetic circuit 8 and the drive coil 7
Is disposed behind the cartridge 1 having a height space obtained by adding the height of the support portion and the thickness of the disk cartridge 1, thereby realizing a low-cost, ultra-thin, and highly efficient linear actuator that generates high thrust.

Effect of the Invention When a linear actuator is formed in the space below the disk cartridge, by providing two pairs of guide shafts (four shafts as shown in the drawing), rotating members are dispersedly arranged in a plane, and the entire height of the support portion is rotated. The height can be suppressed to the sum of the diameter of the member and the diameter of the guide shaft, and a thin linear actuator can be realized.

Furthermore, in addition to the above-described support structure, a magnetic circuit and a drive coil are arranged at the rear of the disk cartridge having a relatively large space including the total height of the support portion and the thickness of the disk cartridge, thereby realizing a thin and high-speed seek with high efficiency. A linear actuator can be realized.

Furthermore, by providing one guide plate having a V-shaped cross section at both ends in the lower space of the disk cartridge below the moving portion, the rotating members are dispersedly arranged in a plane, and the diameter of the rotating member and the guide are adjusted. The entire height of the support portion can be accommodated in an extremely thin space including the plate thickness, and the cost can be reduced because the guide plate can be realized by sheet metal. In addition, by arranging the magnetic circuit and drive coil behind the disk cartridge in the height space that adds the total height of the support part and the thickness of the disk cartridge, it is a low-cost, ultra-thin, highly efficient linear that generates high thrust. An actuator can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a linear actuator according to a first embodiment of the present invention, FIG. 2 is a configuration diagram showing a support structure of the linear actuator according to the first embodiment of the present invention, and FIG. FIG. 4 is a perspective view showing an appearance of a linear actuator according to a second embodiment of the present invention, FIG. 4 is a configuration diagram showing a support structure of the linear actuator according to the second embodiment of the present invention, and FIG. FIG. 6 is a perspective view showing an appearance of a linear actuator according to an embodiment, FIG. 6 is a configuration diagram showing a support structure of a linear actuator according to a third embodiment of the present invention, FIG. FIG. 8 is a configuration diagram showing a support configuration of a conventional linear actuator. 1 ... Disc cartridge, 2 ... Optical head, 3 ...
... moving section, 4 ... moving direction of moving section, 5 ... guide shaft, 6
... Rotating member, 7 ... Drive coil, 8 ... Magnetic circuit, 9
… Pressure leaf spring, 10… Guide plate.

Claims (8)

(57) [Claims] A moving portion linearly reciprocating a predetermined distance below the disk cartridge and the disk cartridge; and a moving portion below the disk cartridge parallel to the reciprocating direction and symmetrically disposed with respect to the moving portion. A first pair of guide shafts, and a second pair of guide shafts disposed symmetrically with respect to the moving portion inside or outside the first pair of guide shafts below the disk cartridge. A rotating shaft on a plane perpendicular to the direction of the reciprocating movement of the moving unit, and rotating in contact with the first pair of guide shafts in a substantially vertical direction facing the disc cartridge by rotating the moving unit; At least three first rotating members mounted on the moving unit that controls the support of the unit, and having a rotating shaft on the plane, and abutting on the second pair of guide shafts while rotating. In the above At least three second rotating members mounted on the moving unit that regulate the support of the moving unit in a substantially horizontal direction perpendicular to the vertical direction; and a second rotating member mounted on the moving unit. Pressurizing means for pressing at least one rotating member with a predetermined pressure to abut against the second pair of guide shafts; and A linear circuit comprising: a magnetic circuit symmetrically disposed; and drive coils fixed to both side surfaces of the moving unit for obtaining a driving force in the direction of the reciprocation by a magnetic field generated in the magnetic circuit. . 2. A moving part linearly reciprocating a predetermined distance below the disk cartridge and the disk cartridge, and a moving part below the disk cartridge parallel to the reciprocating direction and symmetrical with respect to the moving part. A first pair of guide shafts, and a second pair of guide shafts disposed symmetrically with respect to the moving portion inside or outside the first pair of guide shafts below the disk cartridge. A rotating shaft on a plane perpendicular to the direction of the reciprocating movement of the moving unit, and rotating in contact with the first pair of guide shafts in a substantially vertical direction facing the disc cartridge by rotating the moving unit; At least three first rotating members mounted on the moving unit that controls the support of the unit, and having a rotating shaft on the plane, and abutting on the second pair of guide shafts while rotating. In the above At least three second rotating members mounted on the moving unit that regulate the support of the moving unit in a substantially horizontal direction perpendicular to the vertical direction; and a second rotating member mounted on the moving unit. Pressurizing means for pressing at least one rotating member with a predetermined pressure to abut against the second pair of guide shafts; and a direction parallel to the direction of the reciprocating motion outside the disk cartridge and behind the disk cartridge. And a driving circuit fixed to a rear portion of the moving unit that obtains a driving force in the direction of the reciprocating motion by a magnetic field generated in the magnetic circuit. Features a linear actuator. 3. A moving part which linearly reciprocates a predetermined distance below the disk cartridge and the disk cartridge, and a moving part which is parallel to the reciprocating direction and symmetrical with respect to the moving part below the disk cartridge. And the cross-sectional shape of a plane orthogonal to the reciprocating direction is substantially V
A pair of guide plates, each of which has two V-shaped convex side surfaces or two concave side surfaces facing the cartridge, and each of the pair of guide plates has a substantially V-shape. The first of the concave side surfaces having
A pair of guide plate surfaces, a second pair of guide plate surfaces comprising one of the convex side surfaces of each of the pair of guide plates, and a plane perpendicular to the direction of the reciprocating motion of the moving unit. The moving part has a rotation shaft on the upper side, and rotates and abuts on the first pair of guide plate surfaces so as to face the disk cartridge in a substantially vertical direction or a substantially horizontal direction orthogonal to the vertical direction. By having at least three first rotating members mounted on the moving unit that performs support regulation, and having a rotating shaft on the plane, rotating and abutting on the second pair of guide plate surfaces. At least three second units mounted on the moving unit for controlling the support of the moving unit in the substantially vertical direction or the substantially horizontal direction
And at least one of the first rotating member and the second rotating member, which is mounted on the moving part, is pressed by a predetermined pressure, and the first pair of guide plates is pressed. Pressurizing means for abutting a surface or the second pair of guide plate surfaces, and a magnetic circuit arranged outside the disk cartridge and behind the disk cartridge in parallel with the reciprocating direction and symmetrically with respect to the moving portion. And a driving coil fixed to a rear portion of the moving unit that obtains a driving force in the reciprocating direction by a magnetic field generated in the magnetic circuit. 4. The linear actuator according to claim 1, wherein the moving section is an optical head of an optical information recording / reproducing apparatus. 5. The linear actuator according to claim 1, wherein the pressurizing means comprises a spring biasing force provided on a supporting portion of the rotating member. 6. The pair of guide plates have a substantially V-shaped cross section in a plane orthogonal to the reciprocating direction of the moving part, and have two substantially V-shaped convex side surfaces or two concave side surfaces. 4. The linear actuator according to claim 3, wherein the linear actuator is formed of a single sheet metal having a pair of substantially V-shaped ends connected to each other and arranged opposite to the cartridge. 7. The linear actuator according to claim 3, wherein the pair of guide plates have a surface coated with a titanium-based alloy. 8. A pair of guide plates have a substantially V-shaped configuration.
4. The linear actuator according to claim 3, wherein the surface has an elongated hole through which the rotating member passes.