KR19980086187A - Optical Pickup Actuator - Google Patents

Abstract

The present invention is to improve the assembly productivity and regeneration function by simplifying the shape of the yoke plate supporting the lens holder of the optical pickup actuator and the connection structure of the current applied to the tracking coil and the focus coil.

The present invention supports the upper lens holder 20 and the lower lens holder 40 fixing the objective lens 10 to the upper gel holder 30 and the lower gel holder 50 with a suspension wire 36, and the upper lens holder 20 and the lower lens holder 40. The gel holder 30 and the lower gel holder 50 are fixed to the yoke plate 70.

Since the present invention forms only two yokes in the yoke plate 70, the structure is simple and the number of operations for manufacturing the yoke plate 70 is reduced, thereby improving the assembly productivity, and the suspension wire 36 and the tracking coil 62. ) And the flexible PC 64 for applying current to the focus coil 60 are separately connected, so that the connection work of the suspension wire 36 is simple and the tolerance generated during the connection work is reduced.

Description

Optical Pickup Actuator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire driven optical pickup actuator, and in particular, a structure of a lens holder for fixing an objective lens, a yoke plate on which the lens holder is supported, and a structure for connecting a tracking coil and a focus coil fixed to the lens holder to a signal processing unit. It relates to an optical pickup actuator for improving the assembly productivity by simplifying.

In general, an optical pickup actuator constitutes a part of an optical pickup device, and when an error in the optical axis direction or a radial direction error occurs at the focal point of the laser light formed on the recording pit of the disc through the objective lens in the hologram element, A typical wire driving actuator is shown in FIG. 1 as driving means for correcting an error of laser light focus by moving in the radial direction to find a track of the disk and adjusting the size of the focus by moving in the focus direction.

The actuator has a shape in which the lens holder 140 fixing the objective lens 142 is fixed to the yoke plate 110 by the suspension wire 136, and has an objective lens in the center of the lens holder 140. 142 was coupled, and the focus coil 144 was wound around the lens holder 140, and then the tracking coil 146 wound in a rectangular shape on it was pasted thereon. The coil PC 148 was fixed to both sides of the lens holder 140 to connect the tracking coil 146 and the focus coil 144.

In addition, the yoke plate 110 forms a pair of symmetrical outer yokes 114 and attaches and fixes the magnet 118 for generating an electromagnetic force by applying magnetic flux to the tracking coil 146 and the focus coil 144. A pair of inner yokes 112 symmetrically inwardly spaced apart from the outer yoke 114 are bent upwardly from the yoke plate 110 to induce the flow of the magnetic flux of the magnet 118, thereby causing the magnet 118 to be separated. The magnetic flux of the s) crosses the tracking coil 146 and the focus coil 144 strongly horizontally and passes through the planes of the inner yoke 112 and the yoke plate 110 to form the magnetic closure circuit.

In addition, a second yoke 116 is formed at one side edge of the yoke plate 110 to fix the gel holder 120 and the suspension PCB 122 with screws 124, and one end of the suspension wire 136 is a lens. By connecting the coil PC 148 attached to the holder 140 and the other end to the suspension PC 122, the lens holder 140 is lifted and installed by the suspension wire 136, and the suspension from the signal processing unit An electric current applied to the PC 122 is transmitted through the suspension wire 136 to the tracking coil 146 and the focus coil 144. In addition, the suspension wire 134 passes through the inside of the gel holder 120, and the viscous damping gel 121 is injected into the inside of the gel holder 120 so that the negative resonance of the suspension wire 136 is a damping gel ( 121).

However, the conventional optical pickup actuator having the above structure has formed five yokes such as two inner yokes 112, two outer yokes 114, and one second yoke 116 on the yoke plate 110. , They were formed by cutting a part of the yoke plate 110 to bend upward by the bending operation, there was a lot of work for manufacturing the yoke plate (110). In addition, since the conventional actuator supports the lens holder 140 with the suspension wire 136 and applies the current to the tracking coil 146 and the focus coil 144 using the suspension wire 136, the suspension wire ( One end of 136 was connected to the suspension PCB 122 and the other end was connected to the coil PCB 148. This connection structure is complicated, and the number of parts and work is increased, thereby reducing assembly productivity.

In addition, since a large tolerance occurs in the lens holder 140 supported by the suspension wire 136 due to a tolerance during connection, the installation state of the yoke plate 110 on which the lens holder 140 is supported is corrected so that the lens holder ( Although the lens holder 140 is driven in a horizontal or vertical direction with respect to the yoke plate 110 even though the lens 140 is held horizontally, there is a problem that the regeneration function of the actuator is degraded due to a difference between the optical axis directions.

SUMMARY OF THE INVENTION The present invention has been made to solve the conventional problems, and an object of the present invention is to simplify assembly shapes by simplifying the shape of the yoke plate supporting the lens holder of the optical pickup actuator and the connection structure of the current applied to the tracking coil and the focus coil. And to improve the playback function.

The above object is, the upper lens holder and the mounting hole to which the objective lens is assembled; An upper gel holder connected to the upper lens holder by a pair of suspension wires and installed at one side, and forming an upper injection hole into which a damping gel is inserted into a portion connected to the suspension wires; A lower lens holder coupled to a lower side of the upper lens holder, the lower lens holder forming a lower groove corresponding to an upper groove of the upper lens holder; A lower gel holder connected to the lower lens holder by a pair of suspension wires and installed at one side thereof, and forming a lower injection hole into which a damping gel is inserted in a portion connected to the suspension wires and coupling below the upper gel holder; A yoke plate which holds the lower gel holder and forms a first yoke inserted into upper and lower grooves formed in the upper lens holder and the lower lens holder to fix the magnet; It can be achieved by providing an optical pickup actuator consisting of a tracking coil and a focus coil inserted into and fixed in the upper and lower grooves so that the magnetic flux of the magnet fixed to the yoke plate extends.

1 is a perspective view showing a general optical pickup actuator.

Figure 2 is an exploded perspective view of the optical pickup actuator according to the present invention.

Figure 3 is a perspective view showing a coupling state of the optical pickup actuator according to the present invention.

4 is a cross-sectional view of the optical pickup actuator according to the present invention.

<Explanation of symbols for main parts of drawing>

10: objective lens 20: upper lens holder

22: seating hole 24: upper groove

26: first boss 30: upper gel holder

32: upper injection hole 34: second boss

36: suspension wire 40: lower lens holder

42: through hole 44: lower groove

46: first boss ball 50: lower gel holder

52: lower injection hole 54: second boss hole

58: step groove 59: the third boss

60: focus coil 62: tracking coil

64: Flexible PC 70: York Plate

72: first yoke 74: second yoke

76: magnet 78: the third boss ball

80: adjusting sphere

Hereinafter, the present invention will be described in detail by explaining a preferred embodiment of the optical pickup actuator according to the present invention.

2, an upper lens holder 20 having a mounting hole 22 to which the objective lens 10 is assembled and an upper groove 24 open up and down on one side thereof; A pair of suspension wires 36 connected to the upper lens holder 20 to be installed at one side, and an upper injection hole 32 into which a damping gel is inserted into a portion connected to the suspension wires 36. A gel holder 30; A lower lens holder 40 coupled to the lower side of the upper lens holder 20 and having a lower groove 44 corresponding to the upper groove 24 of the upper lens holder 20; A pair of suspension wires 36 are connected to the lower lens holder 40 and installed at one side, and a lower injection hole 52 is formed at the portion connected to the suspension wires 36 to insert a damping gel. A lower gel holder 50 coupled to the gel holder 30 below; The lower gel holder 50 is placed therein, and a first yoke 72 is formed to be inserted into the upper groove 24 and the lower groove 44 formed in the upper lens holder 20 and the lower lens holder 40. A yoke plate 70 fixing the magnet 76; It consists of a tracking coil 62 and a focus coil 60 inserted and fixed in the upper groove 24 and the lower groove 44 so that the magnetic flux of the magnet 76 fixed to the yoke plate 70 extends.

A plurality of first bosses 26 are formed on the bottom of the upper lens holder 20, and a first boss hole 46 into which the first boss 26 is inserted is formed on the upper surface of the lower lens holder 40. The lower lens holder 40 is coupled below the upper lens holder 20. In addition, a plurality of second bosses 34 are formed on a bottom of the upper gel holder 30, and a second boss hole 54 into which a second boss 34 is inserted is formed on an upper surface of the lower gel holder 50. It is formed to couple the lower gel holder 50 to the lower portion of the upper gel holder (30). In addition, a plurality of third bosses 59 are formed on the bottom of the lower gel holder 50, and a third boss hole 78 into which the third boss 59 is inserted is formed in the yoke plate 70 to form a lower gel. The holder 50 is coupled to the yoke plate 70.

In addition, one side of the lower groove 44 of the lower lens holder 40 is provided with a through hole 42 through which both ends of the tracking coil 62 and the focus coil 60 are drawn out to the through hole 42. A flexible PC 64 is connected to both ends of the extracted tracking and focus coil 60 and connected to the signal processor. In addition, the upper gel holder 50 has a stepped groove 58 into which the flexible PC 64 is inserted, so that the flexible PC 64 connected to the tracking coil 62 and the focus coil 60 has an upper gel holder. It is to be fixed between the 30 and the lower gel holder (50).

On the other hand, the first yoke 72 of the yoke plate 70 is formed by cutting the plane and bent upward by the bending operation, and induces the magnetic flux of the magnet 76 at a certain distance from the first yoke 72, The second yoke 74 forming the closed circuit is formed in the same way as the first yoke 72 so as to be formed in the upper groove 24 of the upper lens holder 20 and the lower groove 44 of the lower lens holder 40. To be inserted. Therefore, since the magnetic flux from the magnet 76 passes strongly through the tracking coil 62 and the focus coil 60 by the second yoke 74, a strong electromagnetic force is generated in the tracking coil 62 and the focus coil 60. The sensitivity for driving the upper lens holder 20 and the lower lens holder 40 in the tracking direction and the focus direction is improved. As the magnet 76 uses a product having strong magnetic force, the driving sensitivity of the upper lens holder 20 and the lower lens holder 40 is improved.

The focus coil 60 is wound to surround the second yoke 74, and the tracking coil 62 adheres a pair to one side of the focus coil 60 to attach the focus coil 60 to the upper lens holder 20. Adhesive into the upper groove 24 and the lower groove 44 of the lower lens holder 40.

In addition, the laser beam passes through the objective lens 10 fixed to the upper lens holder 20 at one side of the yoke plate 70, and an adjusting spherical surface 80 for adjusting the installation angle of the yoke plate 70 on the pickup base. ).

In addition, the viscous damping gel is injected into the upper injection hole 32 and the lower injection hole 52 in which the upper gel holder 30 and the lower gel holder 50 are connected to each other, thereby hardening the suspension gel 36. When the negative resonance occurs at the damping gel, the negative resonance is rapidly reduced.

As described above, since the optical pickup actuator of the present embodiment is formed by bending only one first yoke 72 and one second yoke 74 on the yoke plate 70, the manufacturing operation thereof is simplified.

Hereinafter, the operation of the optical pickup actuator having the above configuration will be described with reference to FIGS. 3 and 4.

The optical pickup actuator focuses the laser light irradiated from the laser diode on the objective lens 10 fixed to the upper lens holder 20 to form a focus on the recording pit of the disc. When an error occurs in the focus of the laser light, the signal In the servo controlled by the processing unit, a current is transmitted to the tracking coil 62 and the focus coil 60 through the flexible PC 64 to correct the position of the objective lens 10.

When a current is applied to the tracking coil 62, an electromagnetic force is generated in the tracking direction by the magnetic flux of the magnet 76 according to the direction and magnitude of the current applied to the tracking coil 62 so that the tracking coil 62 is fixed. The upper lens holder 20 and the lower lens holder 40 are driven in the tracking direction. Accordingly, the tracking error is corrected in the objective lens 10 fixed to the upper lens holder 20, so that the recording of the disc can be reproduced satisfactorily. In addition, when a current is applied to the focus coil 60, an electromagnetic force is generated in the focus direction by the magnetic flux of the magnet 76 according to the direction and magnitude of the current applied to the focus coil 60 to fix the focus coil 60. The upper lens holder 20 and the lower lens holder 40 are driven in the focus direction. Accordingly, the focus error is corrected in the objective lens 10 fixed to the upper lens holder 20, so that the recording of the disk can be reproduced satisfactorily.

On the other hand, when the upper lens holder 20 and the lower lens holder 40 supported by the suspension wire 36 vibrate from an external shock or vibration applied to the disk player provided with the optical pickup actuator, the upper gel holder ( 30) and the negative resonance of the suspension wire 36 is rapidly reduced by the viscosity of the damping gel injected into the upper injection hole 32 and the lower injection hole 52 of the lower gel holder 50, the objective lens 10 This makes it possible to stably form the focus of the laser light on the recording pit of the disc.

As described in the above embodiments, the present invention uses the upper lens holder 20 and the lower lens holder 40 to fix the objective lens 10 to the upper gel holder 30 and the lower gel holder by the suspension wire 36. The upper gel holder 30 and the lower gel holder 50 are formed on the yoke plate 70, and only two yokes are formed on the yoke plate 70, so that the structure is simple. Since the number of labors for manufacturing the yoke plate 70 becomes small, assembly productivity is improved. In addition, since the suspension wire 36 supporting the upper lens holder 20 and the lower lens holder 40 and the flexible PC 64 for applying current to the tracking coil 62 and the focus coil 60 are separately connected, the suspension Since the connection work of the wire 36 is simple and the tolerance generated during the connection work is reduced, the tilt generated by the upper lens holder 20 and the lower lens holder 40 is reduced, thereby improving the reproduction function of the optical pickup actuator. There is.

Claims (10)

In the optical pickup actuator for driving the objective lens 10 for forming the focus of the laser light on the disk, An upper lens holder 20 having a mounting hole 22 to which the objective lens 10 is assembled and an upper groove 24 open up and down on one side thereof; A pair of suspension wires 36 connected to the upper lens holder 20 to be installed at one side, and an upper injection hole 32 into which a damping gel is inserted into a portion connected to the suspension wires 36. A gel holder 30; A lower lens holder 40 coupled to the lower side of the upper lens holder 20 and having a lower groove 44 corresponding to the upper groove 24 of the upper lens holder 20; A pair of suspension wires 36 are connected to the lower lens holder 40 and installed at one side, and a lower injection hole 52 is formed at the portion connected to the suspension wires 36 to insert a damping gel. A lower gel holder 50 coupled to the gel holder 30 below; The lower gel holder 50 is placed therein, and a first yoke 72 is formed to be inserted into the upper groove 24 and the lower groove 44 formed in the upper lens holder 20 and the lower lens holder 40. A yoke plate 70 fixing the magnet 76; The tracking coil 62 and the focus coil 60 are inserted into the upper groove 24 and the lower groove 44 so that the magnetic flux of the magnet 76 fixed to the yoke plate 70 extends. Optical Pickup Actuator. The first boss of claim 1, wherein a plurality of first bosses 26 are formed on a bottom surface of the upper lens holder 20, and a first boss 26 is inserted into an upper surface of the lower lens holder 40. The optical pickup actuator, characterized in that to form a ball 46, the lower lens holder 40 is coupled to the upper lens holder (20). According to claim 1, wherein the lower groove 44 of the lower lens holder 40 is formed on one side of the through-holes 42 through which both ends of the tracking coil 62 and the focus coil 60 are drawn out. Optical pickup actuator. The second boss of claim 1, wherein a plurality of second bosses 34 are formed on a bottom surface of the upper gel holder 30, and a second boss 34 is inserted into an upper surface of the lower gel holder 50. The optical pickup actuator, characterized in that to form a ball (54) to combine the lower gel holder (50) with the upper gel holder (30). The third boss hole (78) of claim 1, wherein a plurality of third bosses (59) are formed on a bottom surface of the lower gel holder (50), and a third boss (59) is inserted into the yoke plate (70). And a lower gel holder (50) to the yoke plate (70) to form an optical pickup actuator. The optical pickup actuator according to claim 1, wherein the tracking coil (62) and the focus coil (60) are connected to the signal processing section by a flexible PC (64). The optical pickup actuator according to claim 1 or 6, wherein a stepped groove (58) into which the flexible PC (64) is inserted is formed on an upper surface of the lower gel holder (50). The upper groove 24 of the upper lens holder 20 and the second yoke 74 for forming a magnetic closure circuit by inducing magnetic flux of the magnet 76 on the upper surface of the yoke plate 70. Optical pickup actuator, characterized in that formed to be inserted into the lower groove (44) of the lower lens holder (40). The method of claim 1, wherein the focus coil 60 is wound to surround the second yoke 74, the tracking coil 62 is a pair of bonding to one side of the focus coil 60, characterized in that Optical pickup actuator. According to claim 1, wherein the laser light is passed to the objective lens 10 fixed to the upper lens holder 20 on one side of the yoke plate 70, to adjust the installation angle of the yoke plate 70 on the pickup base Optical pickup actuator, characterized in that for forming the adjustment sphere (80).