JP5829109B2 - Optical pickup objective lens drive device - Google Patents

Description

  The present invention relates to an optical pickup for recording / reproducing information on / from a disc-shaped recording medium such as a DVD or CD, and in particular, a lens holder for holding an objective lens is elastically supported by a plurality of wires. The present invention relates to an objective lens driving device for an optical pickup.

  In this type of objective lens drive device for an optical pickup, a lens holder for holding an objective lens is elastically supported by a plurality (4 or 6) of conductive wires, and the fixed end side of each wire. Is soldered to the back substrate. In a conventional general objective lens driving device, the vicinity of the fixed end of each wire is inserted into a space provided in a support member that is a resin molded product, and this space is filled with a buffering gel. Yes. The back substrate is fixed to the back side of the support member, and this support member is carried on a base member made of a magnetic material. The base member is provided with a magnetic circuit, and a magnet is tightly fixed to the yoke portion of the base member. The objective lens is disposed at a position facing the signal recording surface of a disk-shaped recording medium (hereinafter abbreviated as “disk”). When information is recorded on or reproduced from the disk, a light source (semiconductor) of an optical pickup is used. A light beam emitted from a laser is converged by an objective lens and irradiated onto a signal recording surface of the disk.

  A focus coil and a tracking coil that cross the magnetic flux of the magnetic circuit are attached to the lens holder of the objective lens driving device, and these coils are connected to one end (free end) of the wire, The other end (fixed end) of the wire is connected to the back substrate. Since this back substrate is connected to the external drive circuit via the flexible wiring substrate, an electromagnetic force is generated in the direction along the optical axis of the objective lens by energizing the focus coil via a predetermined wire. Thus, the lens holder can be driven in that direction, thereby enabling focus correction of the objective lens. Similarly, by energizing the tracking coil via another wire, an electromagnetic force can be generated in a direction orthogonal to the optical axis of the objective lens, and the lens holder can be driven in that direction. Tracking correction is possible. In addition, since the attitude of the lens holder is controlled in this way, the wires supporting the lens holder cannot be elastically deformed freely, but the buffering gel filled in the voids of the support member Since the damper effect is exerted on the wire in the void, each wire can be elastically deformed so as not to hinder the movement of the lens holder.

  By the way, in the objective lens driving device configured as described above, a support member that is a resin molded product is attached to the base member, and a wire is inserted into a space of the support member to fill the buffer gel. It is also possible to reduce the cost of the objective lens driving device by omitting this support member. In other words, if the base member is previously formed with a space that performs the same function as the space of the support member, a mounting surface that can fix the back substrate, etc., the support member becomes unnecessary, reducing the component cost and assembly cost. It becomes possible to reduce.

  Therefore, conventionally, the base member of the objective lens driving device is an integral part made of a sheet metal made of a magnetic material, and the base member is provided with a standing wall portion to which the central portion in the longitudinal direction of the rear substrate is bonded and fixed. There has been proposed an optical pickup having a configuration in which a pair of voids opposed to both end portions are provided (see, for example, Patent Document 1). In this structure, the standing wall portion of the base member is erected between a pair of voids, and each void is formed in a shape surrounded by a concave bent portion of the base member. A plurality of wires are inserted into each space, and a buffer gel is filled in each space so that the wire can be damped.

JP 2009-217863 A

  However, in the conventional objective lens driving device disclosed in Patent Document 1, the wire insertion portion provided in the base member is a relatively large space formed by bending a metal plate. There is a problem that the work of filling the buffer gel in the site is troublesome, and the position of the reference surface of the gel (the end surface on the free end side of the wire) is likely to vary. In other words, it is easy to bend a metal plate into a desired shape by bending a metal plate, but if an uncured gel in a sol state is injected into the space, it will easily flow to other locations. The work requires great care and time, and the position of the reference surface of the gel after curing tends to vary, so the accuracy of the effective length of each wire also deteriorates. In addition, the uncured gel injected into the void is cured by irradiating with UV (ultraviolet) light, but since one open end of the void is covered with the back substrate, UV light is not effectively irradiated on the opening end side, and it is difficult to cure the uncured gel in the void in a short time.

  The present invention has been made in view of such a state of the art, and an object of the present invention is to provide an objective lens for an optical pickup that can reduce the parts cost and the assembly cost and can efficiently perform the filling and curing work of the buffer gel. It is to provide a driving device.

In order to achieve the above object, the present invention provides a base member provided with a magnetic circuit including a magnet, a lens holder that holds an objective lens that irradiates a disk-shaped recording medium with a light beam, and the lens holder. In an objective lens driving device of an optical pickup comprising a plurality of conductive wires that are elastically supported and a horizontally long back substrate connected to the fixed end side of these wires, the base member is made of metal. A first bent piece that is formed of an integral part and supports the base member at the center in the longitudinal direction of the rear substrate, and a second bent piece that faces the side edge of the rear substrate at a predetermined interval. And a third bent piece positioned between the side edge of the back substrate and the second bent piece, and the wire is inserted into a through hole formed in the second bent piece. Filled with buffer gel. It is excessive to the third bending piece to face the side end portion of the rear substrate in a position where it does not interfere with the wire inserted through the said holes, said second folding one of the side ends The deformation of was to be regulated.

Thus, the base member of the integral part made of metal is provided with the first bent piece for supporting the back substrate and the second bent piece having the through hole, and a wire is inserted into the through hole for buffering. When the gel agent is filled, it is not necessary to prepare a support member separately, so that the part cost and the assembly cost can be reduced. Moreover, the uncured gel agent injected into the through hole of the second bent piece can be easily filled into the through hole using the surface tension, and the position of the reference surface of the gel agent in the through hole is stable. Easy to make. Moreover, the through hole of the second bent piece faces the back substrate with a predetermined interval, and a wide space is secured also at the opening end of the through hole on the back substrate side. It is possible to efficiently and smoothly carry out the curing by irradiating UV light to the surface. In addition, the third bent piece provided on the base member restricts the side edge portion of the back substrate from being excessively bent toward the second bent piece side. Even if the free end side of the back substrate is pushed in unintentionally, excessive deformation (plastic deformation) of the back substrate can be prevented.

  In the above configuration, the base member is provided with the fourth bent piece protruding above the third bent piece, and the lower space of the fourth bent piece is provided between the side end portion of the back substrate and the through hole. When the extending wire is positioned, it becomes difficult for an operator to touch the fixed end side of the wire when assembling the optical pickup, so that there is no possibility that the fixed end side of the wire is inadvertently plastically deformed.

  In the above configuration, the base member is provided with the fifth bent piece positioned above the lens holder, and if the fifth holder is restricted from excessively rising by the fifth bent piece, the optical The lens holder's posture does not collapse even when vibration or impact is applied to the pickup, so that the required durability can be ensured, and there is no need to prepare a separate cover member for position control of the lens holder. Can be reduced. In this case, when the magnet is tightly fixed to the yoke portion provided on the base member and the fifth bent piece is extended from the yoke portion, the yoke volume is increased and the magnetic efficiency of the magnetic circuit is increased. It is preferable because it increases.

The objective lens driving device for an optical pickup according to the present invention has a first bent piece for supporting a back substrate and a through-hole filled with a buffering gel agent through a base member of an integral part made of metal. Since there is no need to prepare a support member separately, the component cost and the assembly cost can be reduced, which is advantageous for the cost reduction of the entire apparatus. In addition, it is possible to efficiently perform the filling and curing operation of the buffer gel agent by injecting an uncured gel agent into the through hole of the second bent piece and then curing it by irradiating UV light, and the buffer in the through hole. Since the position of the reference surface (end surface on the free end side of the wire) of the gel is not varied, it is easy to improve the accuracy of the effective length of the wire. Furthermore, the third bent piece provided on the base member regulates the side edge of the back substrate so that it does not bend excessively toward the second bent piece side. Even if the free end side of the substrate is pushed in unintentionally, the back substrate can be prevented from being excessively bent and plastically deformed.

1 is a perspective view of an optical pickup according to an embodiment of the present invention. It is the perspective view which looked at this optical pick-up from the back side of FIG. It is a top view of the optical pickup. It is a side view of the optical pickup. It is a bottom view of the optical pickup. It is a disassembled perspective view of this optical pick-up. It is a top view of the chassis with which this optical pick-up is equipped. It is a perspective view which shows the internal structure of this optical pick-up. FIG. 9 is a side view corresponding to FIG. 8. It is the external view seen from the right side of FIG. FIG. 9 is a rear view corresponding to FIG. 8. It is a principal part perspective view corresponding to FIG. 10 and FIG. It is a perspective view of the lens actuator with which this optical pick-up is equipped. It is a top view of the lens actuator. It is a side view of the lens actuator. It is a rear view of the lens actuator. It is a disassembled perspective view of this lens actuator. It is a perspective view of the base member which is a component of this lens actuator. It is a top view of this base member. It is a right view of the base member. It is a left view of this base member. It is a rear view of this base member. It is an expanded view of this base member. FIG. 24 is a plan view corresponding to FIG. 23.

  Embodiments of the invention will be described with reference to the drawings. 1 to 6 show an entire optical pickup according to an embodiment of the present invention.

  The optical pickup 1 shown in these drawings includes a chassis 2 that is a resin molded product, a light emitting and receiving unit 3, a lens actuator 4, a reflection mirror 17 (see FIG. 6), and the like carried on the chassis 2. It is generally configured by an FPC (flexible wiring board) 5 that is led out and connected to an external circuit. The lens actuator 4 that is an objective lens driving mechanism includes a base member 6 provided with a magnetic circuit including a magnet 10, a lens holder 7 that holds the objective lens 8, and one end portion (free end portion) that elastically moves the lens holder 7. And four conductive wires 9 that are supported in a fixed manner, and a horizontally long back substrate 11 to which the other end portion (fixed end portion) of each wire 9 is soldered. The FPC 5 has a long and wide main portion 50 led out of the chassis 2, and the main portion 50 is branched into a first belt portion 51 and a second belt portion 52 in the chassis 2. Yes. Of these two belt-like portions 51 and 52, the first belt-like portion 51 is connected to the back substrate 11, and the second belt-like portion 52 is connected to the light emitting / receiving unit 3.

  The light emitting / receiving unit 3 is integrally provided with a light source (semiconductor laser) and a photodetector. Further, the optical means such as the reflecting mirror 17 is disposed in the optical path between the light emitting / receiving unit 3 and the objective lens 8.

  The chassis 2 includes a first guide portion 21 through which a guide main shaft (not shown) is inserted, and a second guide portion 22 engaged with a guide sub shaft (not shown) in a resilient contact state. It is transported in the radial direction of the disk while being guided by the guide countershaft. In the chassis 2, the rear substrate 11 of the lens actuator 4 is installed at one end where the first guide portion 21 protrudes, and the other end where the second guide portion 22 protrudes. The light emitting / receiving unit 3 is installed in the section. A presser plate 15 made of a thin metal plate is attached to the other end of the chassis 2, and the heat radiation effect on the light emitting / receiving unit 3 is enhanced by pressing the presser plate 15 against the light receiving / emitting unit 3. It has been. 8 to 12 are external views of the optical pickup 1 with the chassis 2 and the pressing plate 15 omitted.

  As shown in the plan view of FIG. 7, the chassis 2 is provided with a storage space 23 having an open top, and the base member 6 of the lens actuator 4 incorporated in the storage space 23 is fixed to the chassis 2 with screws. ing. Further, a groove portion 24 extending in an L shape in plan view along one corner of the storage space 23 is provided in the inner bottom portion of the chassis 2, and as shown by a two-dot chain line in FIG. By inserting (accommodating) the lower end portion of the first belt-like portion 51, the assembly failure of the first belt-like portion 51, which is a concern during assembly, is avoided. One end side of the groove portion 24 extends along one side wall (outer wall portion) 25 of the chassis 2, and the one side wall 25 is set to a height dimension capable of exposing the first belt-like portion 51 of the FPC 5 in the vicinity of the groove portion 24. (See FIG. 4).

  FIGS. 13 to 17 show the lens actuator 4, and FIGS. 18 to 22 show the base member 6 that is a component of the lens actuator 4. The base member 6 is a sheet metal integrated part made of a magnetic material, and is formed by bending a developed metal plate 16 shown in FIGS. The base member 6 has a holder housing portion 6a in which the lens holder 7 is disposed, and a pair of base members 6 fixed to the chassis 2 using two adjusting screws 13 (see FIGS. 1 to 6). An attachment piece 60, a first bent piece 61 that bonds and fixes the central portion in the longitudinal direction of the back substrate 11, and a pair of second bent pieces 62 having a through hole 62 a through which the wire 9 is inserted are provided. . Further, the base member 6 is provided with a third bent piece 63 and a fourth bent piece 64 in the vicinity of the pair of second bent pieces 62, respectively, and at the upper four corners of the holder accommodating portion 6a. A fifth bent piece 65 is provided. 23 and 24, portions corresponding to those in FIGS. 18 to 22 are denoted by the same reference numerals in parentheses.

  The first bent piece 61, the second bent piece 62, and the third bent piece 63 of the base member 6 are upright pieces bent upward, and the mounting piece 60, the fourth bent piece 64, and the fifth bent piece. The bent piece 65 is a protruding piece bent sideways. Then, by appropriately rotating the adjusting screws 13 screwed to the pair of mounting pieces 60, the attitude of the base member 6 with respect to the chassis 2 is changed so that the optical axis tilt adjustment (skew adjustment) of the objective lens 8 can be performed. It has become.

  A pair of upper and lower through holes 62a are formed in the pair of second bent pieces 62, respectively, and as shown in FIGS. 12 and 13, the buffer gel is inserted in the state of the wires 9 inserted into the respective through holes 62a. The agent 12 is filled (in FIG. 1, FIG. 2, FIG. 8, FIG. 10, etc., the buffering gel agent 12 is not shown). Specifically, after filling and filling an uncured gel agent into the through-hole 62a, the gel agent is filled and cured by irradiating it with UV light to obtain the buffer gel agent 12. Yes. Since the buffering gel agent 12 exerts a damper effect on the wire 9 in the through hole 62a, each wire 9 can be elastically deformed so as not to hinder the movement of the lens holder 7. When the central portion in the longitudinal direction of the back substrate 11 is fixed to the first bent piece 61, both side end portions (both end portions in the longitudinal direction) of the back substrate 11 are spaced apart from the second bent piece 62 by a predetermined distance. Therefore, the damping can be effectively performed at a location that is not too close to the fixed end portion of the wire 9. In addition, when performing the filling and hardening operation of the buffering gel agent 12, the gel agent in the sol state can be easily filled into the through holes 62a by utilizing the surface tension thereof, and the through holes 62a of this gel agent can be used. The position of the reference surface in the inside can be stabilized, and moreover, the space between the through-hole 62a and the back substrate 11 can be effectively used to efficiently irradiate UV light.

  The pair of third bent pieces 63 are opposed to the second bent pieces 62 at positions that do not interfere with the wires 9 inserted through the through holes 62a, and the third bent pieces are viewed from the side when the base member 6 is viewed from the side. 63 is erected between the second bent piece 62 and the side edge of the back substrate 11. Therefore, when the central portion in the longitudinal direction of the back substrate 11 is fixed to the first bent piece 61, both side end portions of the back substrate 11 face each other close to the third bent piece 63, and the back substrate The side end of 11 is pushed and bent toward the second bent piece 62, so that the side end is immediately brought into contact with the third bent piece 63 and the position is regulated. In other words, the pair of third bent pieces 63 are for restricting the both side ends (free ends) of the back substrate 11 from being excessively bent in the thrust direction (axial direction) of the wire 9.

  The pair of fourth bent pieces 64 extend laterally from the upper part of the second bent piece 62 so as to cover the third bent piece 63 in the vicinity, and between the second bent piece 62 and the back substrate 11. The extending wire 9 is located in the space below each fourth bent piece 64. That is, if the fixed end side of each wire 9 is exposed in the space between the second bent piece 62 and the back substrate 11 without being shielded, the wire 9 is erroneously plastically deformed during assembly work. Therefore, the wire 9 is protected by these fourth bent pieces 64.

  The base member 6 is provided with a pair of yoke portions 6b that are opposed to each other with the holder housing portion 6a interposed therebetween, and two pieces in a line-symmetrical positional relationship from the upper portion of each yoke portion 6b, a total of four pieces of the fifth fold. A curved piece 65 extends sideways. These fifth bent pieces 65 are for restricting the lens holder 7 from excessively rising even when vibration or impact is applied to the optical pickup 1. Further, the magnet 10 is closely fixed to the opposing surface of each yoke part 6b, and the fifth bent piece 65 is extended from the yoke part 6b. This also contributes to an increase in the yoke volume of the magnetic circuit.

  The objective lens 8 is held at the center of the lens holder 7, and a light beam emitted from the light source (semiconductor laser) of the light emitting / receiving unit 3 is reflected by the reflection mirror 17 or the like when information is recorded or reproduced on the disk. After being incident on the objective lens 8 through the optical means, it is converged by the objective lens 8 and irradiated onto the signal recording surface of the disk. The return light reflected by the signal recording surface of the disk is incident on the objective lens 8 and then photoelectrically converted by the photodetector of the light emitting / receiving unit 3 through the optical means to take out an electric signal.

  A coil (focus coil and tracking coil) 14 that crosses the magnetic flux of the magnetic circuit is attached to the lens holder 7, and these coils 14 are connected to one end (free end) of the wire 9, and the wire The other end portion (fixed end portion) 9 is connected to the back substrate 11. Since the rear substrate 11 is connected to an external drive circuit via the FPC 5, an electromagnetic force is generated in a direction along the optical axis of the objective lens 8 by energizing the focus coil via a predetermined wire 9. Thus, the lens holder 7 can be driven in that direction, and thereby the focus correction of the objective lens 8 can be performed. Similarly, by energizing the tracking coil via another wire 9, it is possible to generate an electromagnetic force in a direction orthogonal to the optical axis of the objective lens 8 and drive the lens holder 7 in that direction. Tracking correction of the objective lens 8 is possible. As described above, since the buffering gel agent 12 exerts a damper effect on the wire 9 in the through hole 62a, each wire 9 elastically supporting the lens holder 7 is in contact with the lens holder 7 when energized. It can be elastically deformed so as not to impede the movement. The total number of through holes 62a corresponds to the number of wires 9 to be used. In this embodiment, a total of four through holes 62a are formed corresponding to the four wires 9. In the case of a configuration in which six are arranged, three through holes 62a (6 in total) may be formed in each second bent piece 62.

  The central portion in the longitudinal direction of the back substrate 11 is bonded and fixed to the first bent piece 61 of the base member 6, and the first strip 51 of the FPC 5 is soldered to the central portion. However, the rear substrate 11 is formed with a protruding portion 11a that protrudes below the base member 6 without being bonded to the first bent piece 61, and the central portion of the rear substrate 11 including the protruding portion 11a is the FPC 5 It is a connection part. Further, wires 9 are soldered to both end portions (both end portions in the longitudinal direction) of the back substrate 11, and these both end portions are free ends that can be bent and deformed so as not to hinder the movement of the wire 9 in the thrust direction. Has become a department. As described above, both side ends of the back substrate 11 are opposed to the second bent piece 62 having the through holes 62a with a predetermined interval, and the third bent piece 63 for position regulation. And are in close proximity.

  Next, the configuration of the FPC 5 will be described in detail. The long and wide main portion 50 of the FPC 5 is led out of the chassis 2, and the tip portion of the main portion 50 is connected to an external circuit (external drive circuit, signal processing circuit, etc.) on the set side by a connector. It becomes a part. The main part 50 is branched into a first belt-like part 51 and a second belt-like part 52, and the first belt-like part 51 is drawn along the side surface 6 c of the base member 6 in the chassis 2 and is substantially perpendicular. After being bent, the back substrate 11 is connected to the central portion from below the free end side through the protruding portion 11a. On the other hand, the second belt-like portion 52 is routed along the upper surface of the chassis 2 and then bent downward and connected to the light emitting / receiving unit 3. As shown in FIG. Is assembled to the chassis 2 together with the light emitting / receiving unit 3 and is in a semi-fixed state.

  As shown in FIGS. 8 to 12, the first band-like portion 51 of the FPC 5 is a tip portion 51 a that extends from the protruding portion 11 a that is a connection location with the back substrate 11 to the side end portion through the bottom of the back substrate 11. And a bent portion 51b bent substantially at a right angle continuously to the tip portion 51a, and an inclined portion 51c extending obliquely upward from the bent portion 51b along one side surface 6c of the base member 6. A portion extending from the inclined portion 51 c to the opposite side of the bent portion 51 b is continued to the second belt-like portion 52. The first belt-like portion 51 is incorporated into the chassis 2 together with the lens actuator 4 in a state where the front portion 51 a is soldered to the central portion of the back substrate 11. At this time, the inclined portion 51 c of the first belt-like portion 51 is disposed in the gap between the one side surface 6 c of the base member 6 and the one side wall 25 of the chassis 2, and thus the first belt-like portion 51 is assembled in the chassis 2. The upper end portion of the inclined portion 51c is positioned above the one side wall 25 of the chassis 2 and is exposed to the side of the optical pickup 1 (see FIG. 4).

  In the optical pickup 1, a control signal for driving the objective lens 8 in the focus direction or the tracking direction (focus correction or tracking correction) is supplied to the wire 9 via the first belt-like portion 51 of the FPC 5. ing. In addition, a power signal and a control signal are supplied to the light emitting / receiving unit 3 via the second strip 52 of the FPC 5, and a signal (electrical signal) detected by the photodetector is set via the second strip 52. Are sent to the signal processing circuit.

  Next, an operation for incorporating the lens actuator 4 into the chassis 2 will be described. In this case, the FPC 5 previously connects the front end portion of the first band 51 to the center of the back substrate 11 and connects the second band 52 to the light emitting / receiving unit 3 and assembled to the chassis 2. In this state, the lens actuator 4 is assembled at a predetermined position in the chassis 2 together with the first belt-like portion 51. That is, the base member 6 of the lens actuator 4 is assembled in the housing space 23 of the chassis 2, and the first strip 51 of the FPC 5 is assembled along the inner wall surface of the chassis 2, and then the adjustment screws are attached to the pair of mounting pieces 60. 13 is screwed to fix the base member 6 to the chassis 2.

  More specifically, when the lens actuator 4 is assembled into the chassis 2, the base member 6 is mounted in alignment with the storage space 23, and the first belt-like portion 51 of the FPC 5 is attached to one side surface 6 c of the base member 6. Assemble it in the chassis 2 so as to wrap it around. In the first band 51, the base end side close to the second band 52 is constrained by the chassis 2, but in the vicinity of the bent portion 51b located in the middle of the base end side and the distal end side (the bent portion 51b and its adjacent portion). (Location) is an easily displaceable portion that is free to move. By inserting this easily displaceable portion into the groove 24 extending along one corner of the storage space 23, the unmovable movement (flicker) of the easily displaceable portion during the assembling work can be achieved. I try to regulate it. The easily displaceable portion of the first belt-like portion 51 and the protruding portion 11a of the back substrate 11 protrude downward from the bottom surface of the base member 6. However, when the base member 6 is mounted in the storage space 23, these easily displaceable portions. By inserting the lower end portion of the projecting portion 11 a into the groove portion 24, the easily displaceable portion of the first belt-like portion 51 is prevented from being sandwiched between the lower surface of the base member 6 and the inner bottom surface of the chassis 2. That is, since the groove portion 24 functions as a clearance space that accommodates the first belt-like portion 51 and the lower end portion of the projecting portion 11a, the easily displaceable portion of the first belt-like portion 51 remains after the base member 6 is mounted in the housing space 23. The state of being opposed to each other without being in contact with the side end portion of the back substrate 11 is maintained. Further, during this assembling operation, the inclined portion 51c of the first belt-like portion 51 is sandwiched between the one side surface 6c of the base member 6 and the one side wall 25 of the chassis 2, and as described above, the inclined portion 51c is regulated. The upper end portion of 51 c is arranged at a position higher than one side wall 25 of the chassis 2.

  In this way, the first belt-like portion 51 is moved into the chassis 2 together with the lens actuator 4 while restricting the position of the easily displaceable portion (the bent portion 51b and its adjacent portion) of the first belt-like portion 51 of the FPC 5 and suppressing the wobbling. When incorporated, the possibility that the easily displaceable portion of the first belt-like portion 51 will sink below the base member 6 is reduced, so that the first belt-like portion 51 is sandwiched between the base member 6 and the inner bottom portion of the chassis 2. It becomes easy to avoid the assembly failure. Note that if the easily displaceable portion of the first band-like portion 51 has sunk under the base member 6, the upper end portion of the inclined portion 51c is not exposed at a predetermined position, so that the first belt-like portion 51 Since the assembly failure is instantly determined, in such a case, the assembly operation can be performed again promptly.

  As described above, in the optical pickup 1 according to the present embodiment, the lens actuator 4 is configured by using the base member 6 that is an integral part obtained by bending a metal plate. A first bent piece 61 for fixing the substrate 11 and a second bent piece 62 having a through hole 62a are provided, and the buffer gel agent 12 is filled with the wire 9 inserted into the through hole 62a. Yes. In other words, the lens actuator 4 does not need to be provided with a separate support member from the base member 6 in order to support the back substrate 11, and accordingly, the parts cost and assembly cost can be reduced accordingly, which is advantageous for cost reduction. It is.

  As described above, the uncured gel agent injected into the through hole 62a of the second bent piece 62 can be easily filled into the through hole 62a using the surface tension, and the through hole 62a. It is easy to stabilize the position of the reference surface of the gel agent in the interior, and a wide space is secured at the opening end of the through hole 62a on the back substrate 11 side, so that the sol gel agent is efficiently irradiated with UV light. Can be made. Therefore, when assembling the lens actuator 4, the filling and curing operation of the buffer gel 12 can be efficiently performed by injecting and curing the uncured gel into the through-hole 62 a, and the standard of the buffer gel 12 is used. Since the position of the surface does not vary, the accuracy of the effective length of the wire 9 can be easily increased.

  Further, the lens actuator 4 can be regulated by the third bent piece 63 provided on the base member 6 so that the side end portion of the back substrate 11 is not excessively bent toward the second bent piece 62 side. Even when the operator unintentionally pushes the free end side (side end portion) of the back substrate 11 when assembling the pickup 1, it is possible to prevent the back substrate 11 from being excessively bent and plastically deformed.

  Further, the lens actuator 4 is provided with a fourth bent piece 64 projecting laterally above the third bent piece 63 on the base member 3, and the back substrate 11 side in the space below the fourth bent piece 64. Since the wire 9 extending between the end portion and the through hole 62a of the second bent piece 62 is disposed, it becomes difficult for an operator to touch the fixed end side of the wire 9 when the optical pickup 1 is assembled. There is no possibility that the fixed end side of the wire 9 is inadvertently plastically deformed.

  Further, in the lens actuator 4, since the plurality of fifth bent pieces 65 provided on the base member 6 restrict excessive rise of the lens holder 4, even if vibration or impact is applied to the optical pickup 1, The posture of the lens holder 4 is not broken. That is, the required durability of the optical pickup 1 is ensured by these fifth bent pieces 65, and there is no need to separately prepare a cover member for restricting the position of the lens holder 4, so that the component cost is reduced. As a result, the assembly cost can be reduced. In addition, since these fifth bent pieces 65 are extended from the yoke portion 6b to which the magnet 10 is closely fixed, the yoke volume is increased and the magnetic efficiency of the magnetic circuit is also increased.

DESCRIPTION OF SYMBOLS 1 Optical pick-up 2 Chassis 3 Light emitting / receiving unit 4 Lens actuator (objective lens drive mechanism)
5 FPC (Flexible Wiring Board)
6 Base member 6b Yoke part 7 Lens holder 8 Objective lens 9 Wire 10 Magnet 11 Rear substrate 11a Protruding part 12 Buffering gel agent 13 Adjustment screw 14 Coil 15 Presser plate 23 Storage space 60 Mounting piece 61 First bent piece 62 Second Bent piece 62a Through-hole 63 Third bent piece 64 Fourth bent piece 65 Fifth bent piece

Claims (4)

A base member provided with a magnetic circuit including a magnet, a lens holder that holds an objective lens that irradiates a disk-shaped recording medium with a light beam, and a plurality of conductive wires that elastically support the lens holder; In the objective lens driving device of the optical pickup provided with a horizontally long back substrate connected to the fixed end side of these wires,
The base member is made of an integral part made of metal, and the base member has a first bent piece for supporting a central portion in the longitudinal direction of the back substrate, and a predetermined interval at a side end portion of the back substrate. A second bent piece facing each other and a third bent piece positioned between the side end portion of the rear substrate and the second bent piece are provided, and a transparent formed in the second bent piece. buffering gels while inserting the wire into the hole and is filled, the third bending piece facing the side end portion of the rear substrate in a position where it does not interfere with the wire that is inserted through the hole And an objective lens driving device for an optical pickup that restricts excessive deformation of the side end portion toward the second bent piece.   The fourth bent piece according to claim 1, wherein a fourth bent piece protruding above the third bent piece is provided on the base member, and a side end portion of the rear substrate is disposed in a lower space of the fourth bent piece. And an objective lens driving device for an optical pickup, wherein the wire extending between the through holes is located.   3. The fifth bent piece according to claim 1 or 2, wherein the base member is provided with a fifth bent piece positioned above the lens holder, and the excessive rise of the lens holder is regulated by the fifth bent piece. An objective lens driving device for an optical pickup.   4. The optical pickup according to claim 3, wherein the magnet is tightly fixed to a yoke portion provided on the base member, and the fifth bent piece extends from the yoke portion. Objective lens drive device.

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