JP2008059625A - Lens holder, and method for assembling lens holder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens holder for optical disk, reading or writing information at a high speed. <P>SOLUTION: In the lens holder 20 used for an optical pickup 10 which reads information recorded in an optical disk or the like, a winding type tracking coil 24 or focusing coil 26 is fixed to the side face of the lens holder 20 perpendicular to the surface of the optical disk and the tangential line of the track of the optical disk. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens holder used in an optical pickup device that reads information recorded on an optical disc and the like, and a method for assembling the lens holder, and more particularly to a highly efficient tracking coil and / or focusing coil using windings. The present invention relates to a lens holder used for driving and a method for assembling the lens holder.

  In recent years, in order to shorten the time required for reading information recorded on an optical disc or writing information on the optical disc, studies on increasing the rotation speed of the optical disc have been made. Along with the increase in the rotation speed of optical discs, the optical pickup device has a high thrust that is unprecedented in order to maintain the tracking performance and focusing performance of the optical pickup device even when vibration is transmitted from the outside to the optical disc drive. And high responsiveness are required.

  In response to the demand for high thrust and high responsiveness for such an optical pickup device, in the lens holder that constitutes the optical pickup device, there is a problem that the number of turns of the tracking coil and focusing coil provided in the lens holder is insufficient. It has become.

  For example, in a conventional lens holder having an FPC board between the lens holder and the coil, when the lens holder is controlled, a current is passed through a tracking coil and / or a focusing coil placed in a magnetic field to generate thrust. Then, before the thrust is transmitted to the lens holder body, there is elasticity and non-linearity due to the FPC board. Due to the presence of elasticity and non-linearity, when the lens holder is driven and controlled, a phenomenon such as a response delay with respect to the drive command occurs. Due to the presence of this response delay, there is a problem that controllability such as tracking, focusing, and tilting of the lens holder in the optical pickup device cannot be improved.

  Further, in order to prevent vibrations caused by thrust generated from a focusing coil that drives the optical pickup lens in the optical axis direction of the lens and a tracking coil that drives the optical pickup lens in a direction perpendicular to the optical axis direction of the lens. Is known (for example, see Patent Document 1). In the present invention, among the lens driving coils, the coil that drives in the optical axis direction of the lens and the coil that drives in the direction perpendicular to the optical axis direction are arranged on the same plane, and the reinforcing material reinforces the coils. Is provided.

  In the lens driving coil described in Patent Document 1, a reinforcing wire is provided across the focusing coil area and the tracking coil area. The lens driving coil is disposed between the magnet and the yoke, and a current is passed from the terminal of the printed coil to the coil pole to obtain thrust in the focusing direction or tracking direction. When a current is passed through this lens driving coil, for example, a rightward thrust is generated in the focusing coil, and a reinforcing material is provided to reinforce the coils even if a downward thrust is generated in the tracking coil. Therefore, harmful vibrations are not generated between 30 and 10 kHz. Further, according to the present invention, by providing a reinforcing wire to the lens driving print coil, it is possible to make the print coil extremely thin and light, and to prevent vibrations caused by different thrusts in the focusing and tracking directions.

  In this lens holder manufacturing method, a multilayer printed coil is first manufactured, and an adhesive is applied to the printed coil, or an adhesive tape is applied to adhere or adhere to the lens holder, and then the coil wiring process is performed. The method of assembling the lens holder by performing the above is used.

  On the other hand, in order to improve the yield by preventing disconnection and short-circuit failure due to external factors, a tracking coil that applies a moving force in the track direction to the lens holder in cooperation with the magnet when energized, and a focusing coil on the lens holder. There is known an optical pickup device having a focusing coil that gives a moving force and a tilting coil that gives a moving force in the tilt direction to the lens holder in cooperation with the magnet when energized (for example, see Patent Document 2). reference.). In this optical pickup device, a tracking coil, a focusing coil, and a tilting coil are formed on a multilayer substrate, and the multilayer substrate is fixed to the lens holder by insert molding.

  In the optical pickup device described in Patent Document 2, when a current is passed through a coil arranged in a magnetic field, the coil obtains a thrust, and the thrust is transmitted to the insert-molded lens holder through the multilayer substrate. Thus, the lens holder is driven. In this optical pickup device, the tracking coil, the focus coil, and the tilting coil are formed on one multilayer substrate, and the multilayer substrate having the function of the coil is insert-molded on the lens holder. Accordingly, since the copper wire is not exposed to the outside, disconnection and short-circuit failure due to external factors do not occur, and as a result, the yield can be improved.

  Further, in this optical pickup device, since the pattern of the multilayer substrate is used as the coil, variation in characteristics such as the resistance value of the coil is suppressed, and as a result, the characteristics of the optical pickup can be made uniform. . In addition, the assembly process that integrates the coil and lens holder can be provided to the next process, eliminating the need for winding and coil assembly and bobbin and lens holder assembly processes, greatly reducing man-hours. It is supposed to be possible.

In addition, in order to provide a lens holder that is lightweight and excellent in controllability, an invention in which a coil is insert-molded on a lens holder or a bobbin is known (see, for example, Patent Documents 3 and 4).
JP-A-8-203103 Japanese Patent Laying-Open No. 2003-272201 (Claim 2) JP 2006-155752 A JP 2006-155753 A

  In the lens driving coil described in Patent Document 1, since the driving coils are reinforced by reinforcing wires formed across the driving coils, even if the printed coil (FPC) is extremely thin and light, it is harmful. It is said that it can suppress the vibration. Further, it is said that the reinforcing wire can be manufactured at the same time as the coil by using the same material as the coil material as the reinforcing wire.

  However, in the lens driving coil described in Patent Document 1, when a current flows through a coil placed in a magnetic field, a thrust is generated in a direction perpendicular to the magnetic field and the current with respect to the coil, and the force is used as a reinforcing material. Then, it is transmitted to the lens holder via the printed coil substrate and the adhesive, and is driven. Therefore, the thrust generated in the coil causes elastic deformation in the printed coil, the adhesive, or the pressure-sensitive adhesive, resulting in a phenomenon that the driving phase is shifted in the high frequency region. If a phase shift occurs during driving, the responsiveness of the lens holder deteriorates, resonance occurs, and the followability to the pits of the disk deteriorates. There was a problem that the processing could not be made faster.

  In addition, this lens driving coil tends to have poor positioning accuracy when the printed coil and the lens holder are bonded or adhered, and thrust crosstalk occurs between tracking and focus control, and the lens holder is controlled. There was a problem of poor quality.

  In addition, this lens driving coil uses a printed coil for the purpose of reducing the size and weight of the optical pickup itself, but due to its structure, such a printed coil has a design change that increases the number of turns of the coil and a stroke design change. Such a problem that the improvement of the above cannot be easily performed.

  Even if a shortage of thrust of the printed coil is detected at the prototype stage, in order to change the design to increase the thrust, redesign of the print pattern, remanufacture of plates, jigs, etc. There is a case where a design change that affects the shape of the entire pickup device is required, which may cause a delay in delivery of the product and an increase in price. In particular, the size of the lens holder used in the optical pickup device is as small as a few millimeters on a side, so the design cannot be easily changed, and there are cases where it later develops into a serious problem. It was.

  Moreover, in this printed coil, since the thin film of the printed circuit board was used for the conductor, the resistance value of the conductor was large. Due to the large resistance value, it is difficult to obtain a large thrust, and it is difficult to reduce the size of the optical pickup device. Moreover, when the resistance value of a conductor is large, the malfunction that heat_generation | fever increases will arise. Furthermore, since the printed coil tends to have a relatively large mass, problems such as deterioration of controllability have occurred. In order to improve the performance of the printed coil, multilayering of the printed coil is essential. However, when multilayering is performed, the printed coil itself is easily cracked, so that the coil is easily disconnected, which is difficult for manufacturing workers. Careful handling was required, and deterioration of product yield was a problem.

  On the other hand, in the optical pickup device described in Patent Document 2, since the position of the driving coil and the position of the lens are separated from each other, even if a thrust acts on the coil, the suspension picks up and responds to the thrust. There is a possibility that the lens will not be displaced and a response delay may occur.

  Further, in this optical pickup device, since the coil pattern is arranged on the multilayer substrate, it is difficult to produce a high density coil in which wires are alternately arranged like a winding type coil. There is a problem that it is difficult to increase the thrust force.

  In addition, since this optical pickup device also has a coil pattern arranged on a multilayer substrate, there is a problem that the resistance value of the coil is large, the amount of heat generated during driving is large, and the design change for enhancing thrust is not easy. ing. In addition, since the coil pattern is arranged on the multilayer substrate, the thrust generated in the coil pattern is transmitted to the lens holder through each multilayer substrate and its joint, so that the deflection of the multilayer substrate, the nonlinearity of the joint, etc. Due to the influence, the frequency response related to the force transmission is deteriorated and the controllability of the lens holder is deteriorated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lens holder that enables high-speed reading or writing of information in an optical disc apparatus.

  Another object of the present invention is to provide a lens holder for an optical disc apparatus having excellent controllability of tracking drive, focusing drive, and tilting drive at a low cost.

  Another object of the present invention is to easily position and bond a winding type tracking coil and / or a winding type focusing coil to the lens holder in order to provide a lens holder of an optical disc apparatus with excellent controllability at low cost. It is providing the lens holder which can do.

  Another object of the present invention is to provide a lens holder assembling method in which a winding type tracking coil and / or a winding type focusing coil is easily positioned and bonded to the lens holder.

  A lens holder of the present invention for solving the above-mentioned problems is used in an optical pickup device for reading information recorded on an optical disk, and has a side surface perpendicular to the surface of the optical disk and the tangent line of the track of the optical disk. A lens holder having a protruding boss for positioning a winding type tracking coil and / or a winding type focusing coil is provided on the side surface.

  In addition, a lens holder of the present invention for solving the above-described problems is used in an optical pickup device that reads information recorded on an optical disc, and is perpendicular to the surface of the optical disc and the tangent line of the track of the optical disc. In the lens holder having a side surface, a winding type tracking coil and / or a winding type focusing coil are bonded to the side surface.

  In the lens holder of the present invention, the winding-type tracking coil has a substantially rectangular parallelepiped shape that is long in a direction perpendicular to the surface of the optical disc, and the winding-type focusing coil has a normal to the track normal of the optical disc. It is preferably a substantially rectangular parallelepiped shape that is long in a parallel direction.

  The lens holder of the present invention can be configured such that a hollow portion for positioning is provided at the center of the winding tracking coil and / or the winding focusing coil.

  In the lens holder of the present invention, the positioning hollow portion can be configured to have a substantially square shape.

  In the lens holder of the present invention, the end face of the winding type tracking coil and / or the winding type focusing coil can be configured to be exposed on the side surface of the lens holder.

  The lens holder of the present invention can be configured to include a boss for positioning the center portion of the winding type tracking coil and / or the winding type focusing coil.

  In the lens holder according to the aspect of the invention, it is preferable that the boss is a boss including a plurality of substantially cylindrical convex portions.

  A lens holder assembling method of the present invention for solving the above-described problems is an assembling method of a lens holder used in an optical pickup device for reading information recorded on an optical disc. A step of positioning a winding-type tracking coil and / or a winding-type focusing coil on a boss protruding from a side surface; and a step of temporarily bonding the winding-type tracking coil and / or the winding-type focusing coil to the lens holder Fixing the terminal plate to the lens holder; connecting the lead wire of the winding type tracking coil and / or winding type focusing coil to the terminal plate; and the winding type tracking coil and / or Apply adhesive to the wound focusing coil and the lens holder And extent, characterized in that it comprises a, and curing the adhesive.

  According to the lens holder of the present invention, the optical disk has a side surface perpendicular to the surface of the optical disk and the tangent line of the track of the optical disk, and a protrusion for positioning the winding type tracking coil and / or the winding type focusing coil on the side surface. Since the boss is provided, it is possible to perform adhesion after fitting the winding type tracking coil and / or the winding type focusing coil to the lens holder, and the winding type tracking coil and / or the winding type to the lens holder. The focusing coil can be easily positioned and bonded.

  Further, according to the lens holder of the present invention, the structure has a side surface perpendicular to the surface of the optical disk and the tangent line of the track of the optical disk, and the winding type tracking coil and / or the winding type focusing coil are bonded to the side surface. Therefore, for example, compared to the case where the focusing coil is provided on the lens surface of the lens holder, it is possible to increase the degree of freedom with respect to the arrangement of the focusing coil. As a result, increase / decrease in the number of turns in the prototype stage, increase / decrease in the outer dimensions of the coil, increase / decrease in the inner dimensions of the coil, increase / decrease in the effective length of the coil, increase / decrease in the coil diameter, change of the lens holder stroke, etc. The change can be made relatively easily within the range of the thickness of the lens holder or the size of the side surface of the lens holder. As a result, it is possible to prevent an increase in development costs and prevent an extension of the development period.

  Further, according to the lens holder of the present invention, the end face of the winding type tracking coil and / or the winding type focusing coil is exposed on the side surface of the lens holder, so that many conductors are concentrated in a region where the magnetic field is strong. The thrust generated by the coil can be increased, and the controllability of the lens holder can be improved. As a result, focusing or tilting controllability in the lens holder can be improved, and information reading or information writing in the optical disc apparatus can be performed at high speed.

  Further, according to the lens holder of the present invention, since the coil and the lens holder are directly bonded, the connection rigidity between the coil and the lens holder can be increased. Thereby, the frequency responsiveness at the time of driving a lens holder improves, and the controllability of a lens holder can be improved. Moreover, in the lens holder of the present invention, since the winding type coil is directly bonded to the lens holder, the multilayer substrate used as a conventional coil is not necessary.

  Therefore, according to the lens holder of the present invention, the lens holder can be reduced in weight, and the controllability of the lens holder can be improved. In addition, as described above, the specification change that increases the number of turns of the winding can be easily performed, so that it is possible to flexibly and quickly cope with the change in the power supply voltage specification and the drive circuit specification. Therefore, since it becomes possible to provide a lens holder that always has a thrust that meets the specifications, the tracking drive, focusing drive, or tilting drive controllability in the optical disc apparatus can be maintained in a good state. It is possible to read information or write information on the optical disc apparatus at high speed.

  In addition, the lens holder of the present invention includes a substantially rectangular parallelepiped winding type tracking coil which is perpendicular to the surface of the optical disk, a side surface perpendicular to the surface of the optical disk and the tangent of the track of the optical disk, and a track of the optical disk. Since a wire-shaped focusing coil having a substantially rectangular parallelepiped shape that is long in a direction parallel to the normal line is bonded, more conductors can be placed in a limited magnetic field. Thereby, since the thrust generated by the tracking coil can be increased, the controllability of tracking in the lens holder can be improved. As a result, information reading or information writing in the optical disc apparatus can be performed at high speed.

  Further, according to the lens holder of the present invention, since the positioning hollow portion is provided at the center of the winding type tracking coil and / or the winding type focusing coil, the positioning accuracy of the coil with respect to the lens holder is improved. Further, crosstalk between the tracking drive, the focusing drive, and the tilting drive can be reduced, and the controllability of the lens holder can be improved. As a result, focusing or tilting controllability in the lens holder can be improved, and information reading or information writing in the optical disc apparatus can be performed at high speed.

  Since the winding type coil is wound from the inside toward the outside, the shape of the central part of the coil is not changed even if the number of coils is changed. Therefore, according to the lens holder of the present invention, increase / decrease in the number of turns in the prototype stage, increase / decrease in the outer dimensions of the coil, increase / decrease in the inner dimension of the coil, increase / decrease in the effective length of the coil, increase / decrease in the coil wire diameter, lens Design changes such as increase or decrease of the stroke of the holder can be easily performed within the range of the thickness of the lens holder or the size of the side surface of the lens holder. As a result, even if there is a change in the winding specification, it is possible to prevent an increase in development cost and to prevent an extension of the development period.

  In addition, according to the lens holder of the present invention, the positioning accuracy of the coil with respect to the lens holder is improved because the center portion of the winding type tracking coil and / or the winding type focusing coil is provided with a substantially rectangular positioning hollow portion. Thus, crosstalk among the tracking drive, the focusing drive, and the tilting drive can be reduced, and the controllability of the lens holder can be improved. As a result, focusing or tilting controllability in the lens holder can be improved, and information reading or information writing in the optical disc apparatus can be performed at high speed.

  Further, according to the lens holder of the present invention, the end face of the winding type tracking coil and / or the winding type focusing coil is exposed on the side surface of the lens holder, so that many conductors are concentrated in a region where the magnetic field is strong. The thrust generated by the coil can be increased, and the controllability of the lens holder can be improved. As a result, focusing or tilting controllability in the lens holder can be improved, and information reading or information writing in the optical disc apparatus can be performed at high speed.

  Further, according to the lens holder of the present invention, the boss for positioning the winding type tracking coil and / or the winding type focusing coil is provided on the surface of the optical disk and the side surface of the lens holder perpendicular to the tangent to the track of the optical disk. Therefore, it is possible to perform adhesion after fitting the winding type tracking coil and / or the winding type focusing coil to the boss of the lens holder, facilitating the positioning of the lens holder and increasing the positioning accuracy. It becomes possible to improve. Further, the contact area between the winding type tracking coil and / or the winding type focusing coil and the adhesive can be increased, and the bonding can be reliably performed.

  Further, according to the lens holder of the present invention, the boss for positioning the center portion of the winding type tracking coil and / or the winding type focusing coil is formed on the side surface of the lens holder, and the boss is formed with a plurality of substantially cylindrical projections. Since it is comprised from the part, it can make it easy to fill an adhesive agent between a winding type coil and a lens holder, maintaining the positioning accuracy of a winding type coil and a lens holder. Furthermore, without changing the shape of the boss of the lens holder, design changes such as increase / decrease in the number of coil turns, increase / decrease in coil outer dimensions, increase / decrease in coil diameter, and increase / decrease in lens holder stroke at the prototype stage. This can be easily performed within the range of the thickness of the lens holder or the size of the side surface of the lens holder. As a result, even if the specification is changed, it is possible to prevent an increase in the development cost of the optical pickup and to prevent the development period from being extended.

  Further, according to the lens holder of the present invention, since the winding type tracking coil and / or the winding type focusing coil are directly bonded to the lens holder, compared with the conventional optical pickup using an FPC or a multilayer substrate. It is possible to wind as many coils as the material such as FPC, and it is possible to increase the thrust during driving and improve the controllability of the lens holder.

  In addition, according to the lens holder of the present invention, since a coil of a winding type is used for each coil, it is possible to prevent troubles caused by damage or disconnection of the substrate that has occurred in the FPC or the multilayer substrate. Further, since no FPC or multilayer substrate is used, the lens holder can be reduced in size and weight, and the rigidity of the lens holder can be increased.

  In addition, according to the lens holder of the present invention, it is possible to use a high-density coil obtained by performing compression processing or the like on each coil. This reduces the size of the lens holder and manages the shape of the coil from a conventional barrel shape to a good shape close to a rectangular parallelepiped, improving the positioning accuracy of each coil and improving the thrust generated by each coil. Is possible.

  According to the lens holder assembling method of the present invention, the step of positioning the winding type tracking coil and / or the winding type focusing coil on the protruding boss on the side surface of the lens holder, the winding type tracking coil, and / or Alternatively, a step of temporarily bonding the winding type focusing coil to the lens holder, a step of fixing the terminal plate to the lens holder, and a step of connecting the lead wire of the winding type tracking coil and / or the winding type focusing coil to the terminal plate And the lens holder is assembled through the step of applying an adhesive to the winding type tracking coil and / or the winding type focusing coil and the lens holder, and the step of curing the adhesive. It is possible to easily assemble lens holders with high connection rigidity between lens holders. That. As a result, it is possible to provide a lens holder having a high natural frequency, good frequency response, and good controllability at low cost.

  The best mode for carrying out the present invention will be described below with reference to the drawings. The technical scope of the present invention is not limited to the following embodiments.

  FIG. 1 is a perspective view of an optical pickup device provided with a lens holder according to the present invention as viewed from the optical disk side. An optical pickup device 10 according to the present invention is a device that can be used for an optical disk driver mounted on an electronic device such as a personal computer, and is controlled so as to move in the Tr direction in FIG. Is the body.

  As shown in FIG. 1, the optical pickup device 10 includes a lens holder 20 that holds a lens 22 disposed so as to face the optical disc, and the lens holder 20 in the tracking direction of the optical disc (Tr direction shown in FIG. 1). Six suspension wires 14 that can be slightly displaced in the focusing direction (Fo direction shown in FIG. 1), and are supported so as to be capable of turning by a small angle in the tilting direction (Ti direction shown in FIG. 1). I have. In the present invention, the number of suspension wires is not limited. For example, four suspension wires may be provided in accordance with requirements such as the number of electrodes.

  The optical pickup device 10 is provided with a first magnet 30 and a second magnet 32 that generate a magnetic force for generating a driving force for tracking, focusing, and tilting. It is fixed to. The damper base 12 holds one end of six suspension wires 14.

  In the present invention, in order to obtain a desired line of magnetic force in a limited space, the first magnet 30 and the second magnet 32 are polarized magnets having a plurality of magnetic poles in one plane.

  Although not shown in FIG. 1, the optical pickup apparatus 10 includes a semiconductor laser that generates a laser beam, a beam splitter that branches the laser beam emitted from the semiconductor laser, and a laser beam that receives the laser beam and corresponds to the intensity of the light. Monitoring device that outputs electrical signals, collimating lenses that convert the laser beam into parallel light, a rising mirror that changes the direction of the laser beam, and a photodiode that receives the laser beam reflected by the optical disk and converts it into an electrical signal And are provided.

  The lens 22 can focus the laser beam and irradiate the optical disk. Then, the light reflected from the optical disk again passes through the lens 22 to become parallel light, is reflected by the rising mirror, passes through the collimating lens, passes through the beam spirit, forms an image on the photodiode, and is electrically Converted to a signal.

  The optical pickup device 10 is a tracking drive mechanism that drives the lens holder 20 by a minute displacement in the normal direction of the track of the optical disc (Tr direction shown in FIG. 1) in order to follow the pit track shake due to the eccentric motion of the optical disc. Is provided. This tracking drive mechanism is composed of a first magnet 30, a second magnet 32, and a tracking coil 24.

  Further, in order to focus the laser beam on the pits of the optical disk, a focusing drive mechanism is provided for driving the lens holder 20 by a minute displacement in a direction perpendicular to the surface of the optical disk (Fo direction shown in FIG. 1). This focusing drive mechanism is composed of a first magnet 30, a second magnet 32, and a focusing coil 26.

  Further, in order to follow the swing of the pit track due to the waviness of the optical disc, the tilting drive that rotates the lens holder 20 by a minute angle around an axis parallel to the tangential direction of the track of the optical disc (Ti direction shown in FIG. 1). A mechanism is provided. This tilting drive mechanism includes a first magnet 30, a second magnet 32, and a focusing coil 26.

  FIG. 2 is an external perspective view of the lens holder according to the present invention. FIG. 3 is a view explicitly showing the adhesive 27 that bonds the side surface of the lens holder shown in FIG. 2 to the tracking coil and the focusing coil.

  As shown in FIG. 2, the two surfaces (surface Q and surface P) of the lens holder 20 perpendicular to the surface of the optical disk and the tangent to the track of the optical disk are perpendicular to the surface of the optical disk (in FIG. The tracking coil 24 having a substantially rectangular parallelepiped shape that is long in the Fo direction) and having a substantially rectangular hollow portion for positioning at the center, and the normal line (Vr and Tr directions shown in the figure) of the track of the optical disk. A focusing coil 26 having a substantially rectangular parallelepiped shape that is long in the parallel direction and having a substantially rectangular hollow portion for positioning at the center is bonded using an adhesive 27 (see FIG. 3).

  As shown in FIG. 3, the adhesive 27 is applied so as to be in contact with the side surface of the lens holder 20, the hollow portions and the outer periphery of the tracking coil 24 and the focusing coil 26, and fixes each coil and the lens holder 20.

  As shown in FIGS. 2 and 3, the tracking coil 24 and the focusing coil 26 are winding coils around which conductive wires are wound. By using high-density coils that have been subjected to compression processing or the like as these coils, it is possible to further increase the density and size of the coils, and to manage the shape of the coils closer to a rectangular parallelepiped. It becomes possible.

  When a thermosetting adhesive is used as an adhesive for bonding each coil and the lens holder, it is necessary to maintain the temperature at about 100 ° C. for about 30 minutes when curing the adhesive. It is preferable to use a wire provided with a highly heat-resistant resin film or the like.

  Further, lead wires 28 taken out from the two tracking coils 24 and the two focusing coils 26 are provided on two opposite surfaces of the lens holder 20 that are perpendicular to the normal surface of the optical disk surface and the optical disk track. A first terminal plate 40 and a second terminal plate 42 which are connected to the terminal 44 and connect and relay each coil in series or in parallel depending on the application are bonded. The first terminal plate 40 and the second terminal plate 42 are substrates that function as terminals for relaying lead wires taken out from the tracking coil 24 or the focusing coil 26. In the embodiment shown in FIG. 2, the first terminal plate 40 and the second terminal plate 42 are positioned on a terminal plate positioning boss 46 protruding from the lens holder 20.

  The currents supplied to the two tracking coils 24 and the two focusing coils 26 are supplied from the damper base 12 via the suspension wire 14, the first terminal plate 40 and the second terminal plate 42 to the two tracking coils. 24 and two focusing coils 26 are supplied.

  4 is a cross-sectional view of the lens holder 20, the first terminal plate 40, and the second terminal plate 42 when the winding type tracking coil 24 and the winding type focusing coil 26 are bonded to the lens holder according to the present invention. FIG. The figure shows the AA cross section of FIGS. 2 and 3.

  As shown in FIG. 4, on the two side surfaces (surface Q and surface P) of the lens holder 20, a protruding boss 36 for positioning the tracking coil 24 and a protruding boss for positioning the focusing coil 26 are provided. 36.

  In the embodiment shown in FIG. 4, the boss 36 positions the center of the winding type tracking coil 24 and the winding type focusing coil 26. However, the present invention is limited to the boss that positions the center of the coil. Not what you want. In addition, since a winding type coil normally winds a conducting wire with the inside as a reference, the inside of the coil has excellent dimensional accuracy. Therefore, it is convenient to provide a substantially rectangular hollow portion suitable for positioning at the center of the coil and position the coil using this hollow portion and the boss 36.

  Further, when the number of coils and the wire diameter are changed, the outer dimensions change, but the dimensions inside the coils do not change. Therefore, by positioning the central portion of the coil using the boss 36, there is an advantage that it is easy to maintain the positioning accuracy of the winding type tracking coil 24 and the winding type focusing coil 26 regardless of the coil specifications.

In the embodiment shown in FIG. 4, the boss 36 is composed of six substantially cylindrical convex portions, but the present invention does not limit the number or shape of the bosses. In general, since the lens holder 20 is manufactured by injection molding of resin, the processing and management of a mold for forming the convex portion on the side surface of the lens holder 20 can be performed by making the boss 36 a cylindrical convex portion. It becomes easy. Further, by positioning the hollow portion of the coil with six thin bosses having a diameter of about 0.2 mm to 0.5 mm, the contact area between each coil and the lens holder 20 and the adhesive is increased. Adhesion with the holder 20 can be made more reliable. The boss 36 may be a cylindrical boss as shown in FIG. 4, may be tapered to facilitate coil insertion, or may have a tip formed in a spherical shape. Alternatively, a prismatic shape or a pyramid shape may be formed. At this time, if the diameter of the tip of the boss 36 is made larger than the diameter of the body of the boss 36, the coil 70 inserted into the boss 36 can be prevented from coming off.
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  Further, as shown in FIG. 4, a winding type tracking coil 24 and a winding type focusing coil 26 are exposed and bonded to the side surface of the lens holder 20, so that many conductors are concentrated in an area where the magnetic field is strong. Since the thrust generated by the coil can be increased, the controllability of the lens holder can be improved.

  The two tracking coils 24 and the two focusing coils 26 are adhered to the two side surfaces (surface Q and surface P) of the lens holder 20 at positions that are point-symmetric with respect to the center Z of the lens holder 20. The reason why the two focusing coils 26 are arranged point-symmetrically with respect to the center Z is to realize focusing driving and tilting driving using the two focusing coils 26. Note that the tracking coil or the focusing coil does not necessarily have to be two sets, and may be one set, or even if three or more sets are provided, the object of the present invention can be achieved.

  Further, as shown in FIG. 4, the tracking coil 24 and the focusing coil 26 are directly bonded to the side surface of the lens holder 20. Therefore, when a control current is passed through the tracking coil 24 or the focusing coil 26 placed in the magnetic field, the coil generates a thrust in a direction perpendicular to the direction of the magnetic field and the current. The thrust of this coil is directly transmitted to the material (for example, resin) which comprises the lens holder 20, and can drive the lens holder 20.

  When the lens holder 20 is driven for tracking, for example, in-phase currents are supplied to the two tracking coils 24. Then, since the two tracking coils 24 generate thrust in the same tracking direction (Tr direction shown in FIG. 1), the lens holder 20 is tracking-driven in the Tr direction. Therefore, it is possible to perform drive control for causing the laser beam to follow the pit track of the optical disk.

  When the lens holder 20 is driven to focus, for example, in-phase currents are supplied to the two focusing coils 26. Then, the two focusing coils 26 generate thrust in the same focus direction (Fo direction shown in FIG. 1), and drive the lens holder 20 in the Fo direction. Therefore, it is possible to perform drive control for focusing the laser beam on the pit of the optical disk.

  Further, when the lens holder 20 is tilted, for example, currents of opposite phases are passed through the two focusing coils 26. Then, the two focusing coils 26 generate thrust in different directions, and tilt the lens holder 20 around Ti. Therefore, it is possible to perform drive control for causing the laser beam to follow the pit track of the optical disk.

  Next, an assembly method for bonding the tracking coil 24, the focusing coil 26, the first terminal plate 40, and the second terminal plate 42 to the lens holder 20 will be described.

  First, a manufacturing method of the tracking coil 24 and the focusing coil 26 will be schematically described. The tracking coil 24 and the focusing coil 26 are wound by a predetermined number of turns from the center of the coil by setting a winding jig on the winding machine. The hollow portions and end faces of the tracking coil 24 and the focusing coil 26 are portions that are in contact with a jig (bobbin) for winding, and the hollow portion of the coil particularly corresponds to a reference position for starting winding. To do. Therefore, even if the wire diameter and the number of coils of the coil are slightly different, the dimensions of the hollow portion of the coil are the same, and the accuracy of the dimension is good.

  The coil wire has an insulating enamel layer around a conductor (core wire) with low electrical resistance, and the enamel layer is made of nylon or the like for adjusting the shape of the air-core coil. It has a fusion layer. When winding a coil of a winding type, a predetermined number of turns are wound using a jig while keeping the wire heated to a temperature at which the fusion layer melts. In the state where the winding process of the wire is completed, the adjacent wires are fused by the fusion layer. Therefore, when the wound coil is cooled and removed from the bobbin, the air-core coil is completed.

  Next, the winding type tracking coil 24 and the winding type focusing coil 26 are positioned on the boss 36 present on the side surface of the molded lens holder 20. At this time, an adhesive for temporary fixing is applied in advance to the coil mounting portion of the lens holder 20, and the tracking coil 24, the focusing coil 26, and the lens holder 20 are temporarily bonded. Become.

  Next, the terminal plate 40 and the terminal board 42 are fixed to the side surface of the lens holder 20. In the embodiment shown in FIGS. 2 to 4, the terminal board 40 and the terminal board 42 are positioned using the terminal board positioning boss 46 to facilitate the assembly. The terminal plate 40 and the terminal board 42 and the lens holder 20 may be fixed by using an adhesive method, or by using a method such as caulking, fitting, or welding. The fixing method is not limited.

  Next, the lead wires of the tracking coil 24 and the focusing coil 26 are connected to the terminals 44 of the terminal plates 24 and 26 by soldering. Then, an adhesive for coupling the tracking coil 24 and the focusing coil 26 to the lens holder 20 is applied, and a process for curing the adhesive is performed. When a thermosetting adhesive is used as the adhesive, the lens holder 20 after application of the adhesive is placed in a furnace and heat-treated.

  In this way, the lens holder 20 in which the tracking coil 24, the focusing coil 26, the first terminal plate 40, and the second terminal plate 42 are bonded to the lens holder 20 is completed.

  Next, variations in the shape of the boss for positioning the lens holder 20 and the coil 70 will be described.

  FIG. 5 is a perspective view showing an embodiment in which a boss 36 composed of six columnar convex portions is used as a boss for positioning the hollow portion 72 existing at the center of the coil 70.

  As shown in FIG. 5, a hollow portion 72 for positioning is provided at the center of a substantially rectangular parallelepiped coil 70 (tracking coil or focusing coil). In the example shown in the figure, in order to position the coil 70 on the side surface of the lens holder 20, the shape of the hollow portion 72 provided in the coil 70 is a substantially square shape. By positioning the hollow portion 72 of the coil 70 using the boss 36 composed of six cylindrical convex portions, in addition to the positioning in the X direction and the Y direction shown in FIG. It is possible to do. Moreover, the mass of the lens holder 20 can be lightened by using the small boss | hub 36 comprised from a cylindrical convex part.

  FIG. 6 is a perspective view showing an embodiment in which a boss 36 composed of six columnar convex portions is used as a boss for positioning the outer peripheral portion of the coil 70.

  As shown in FIG. 6, the coil 70 and the lens holder 20 can be positioned using the outer periphery of the coil 70. In the case of this embodiment, in addition to the positioning in the X direction and the Y direction shown in the figure, positioning around Θ can be performed.

  FIG. 7 is a perspective view showing an embodiment in which a boss 36 composed of four columnar convex portions is used as a boss for positioning the hollow portion 72 existing in the central portion of the coil 70.

  As shown in FIG. 7, in order to position the coil 70, a boss 36 composed of four cylindrical convex portions may be used. In this case, the bosses 36 may be disposed at the four corners of the hollow portion 72. In the case of this embodiment, in addition to the positioning in the X direction and the Y direction shown in the figure, positioning around Θ can be performed.

  As the shape of the coil, it is convenient to use a substantially rectangular parallelepiped shape as shown in FIGS. 5 to 7 in terms of magnetic field space, but the shape is not necessarily limited to the substantially rectangular parallelepiped shape, and will be described with reference to FIG. 8 below. Such an oval column shape may be used, or a rhombus column shape, a triangular column shape, or a column shape may achieve the object of the present invention. Further, the shape of the hollow portion of the coil and the shape of the boss are not limited to a quadrangular shape.

  FIG. 8 is a perspective view of another embodiment showing the relationship between the ellipsoidal columnar coil 74 and the boss 36.

  As shown in FIG. 8, a positioning hollow portion 76 is provided at the center of an elliptical columnar coil 74 (tracking coil or focusing coil). In the example shown in the figure, the hollow portion 76 provided in the coil 74 is formed in an oval shape so that the coil 74 is fitted and positioned with the two cylindrical bosses 36 provided on the side surface of the lens holder 20. Yes. In the example shown in the figure, the hollow portion 76 is formed in an oval shape so that positioning around Θ can be performed in addition to the positioning in the X direction and the Y direction shown in the figure.

  FIG. 9 is a cross-sectional perspective view of another embodiment showing the relationship between a substantially rectangular parallelepiped coil 70 and a rectangular parallelepiped boss 92.

  In the example shown in FIG. 9, a boss 92 composed of a rectangular parallelepiped convex portion is provided on the side surface of the lens holder 20 as a boss for positioning the hollow portion 72 present at the center of the substantially rectangular parallelepiped coil 70. It is a perspective view which shows a form. By making the shape of the hollow portion 72 and the boss 92 into a substantially square shape, in addition to the positioning in the X direction and the Y direction shown in FIG.

  FIG. 10 is a cross-sectional perspective view of another embodiment showing the relationship between a substantially rectangular parallelepiped coil 70 and a rectangular parallelepiped boss 94 with four corners removed.

  In the example shown in FIG. 10, as a boss for positioning the hollow portion 72 existing in the central portion of the substantially rectangular parallelepiped coil 70, a boss 94 constituted by a rectangular parallelepiped convex portion from which four corners are removed is used as a side surface of the lens holder 20. It is a perspective view which shows embodiment provided in.

  The hollow portion 72 of the coil 70 has a substantially rectangular shape, and the boss 94 has a rectangular parallelepiped shape with the four corners removed, whereby interference between the fan-shaped portions at the four corners of the hollow portion 72 of the coil 70 and the boss 94 occurs. The positioning can be performed while avoiding the above. Therefore, in addition to the positioning in the X direction and the Y direction shown in the figure, positioning around Θ can be performed.

  FIG. 11 is a cross-sectional perspective view of another embodiment showing the relationship between the substantially rectangular parallelepiped coil 70 and the boss 100.

  The example shown in FIG. 11 is an embodiment in which the outer periphery of a substantially rectangular parallelepiped coil 70 is fitted and positioned with a boss 100 having a substantially rectangular parallelepiped inner surface provided on the side surface of the lens holder 20. In the example shown in the figure, by aligning the inner surface shape of the boss 100 with the outer peripheral shape of the coil 70, in addition to the positioning in the X direction and the Y direction shown in the figure, positioning around Θ can be performed.

  Also in this embodiment, the coil shape is preferably a substantially rectangular parallelepiped shape, but is not necessarily limited to a substantially rectangular parallelepiped shape, and may be an elliptical columnar shape as shown in FIG. The object of the present invention can also be achieved by a rhombus column shape, a triangular prism shape, or a cylindrical shape.

  4 to 11, the diameter of the tip of the boss 36 (tip on the side where the coil is inserted) or the tip of the boss 92, 94, 100 (tip where the coil is inserted). Part) is larger than the diameter or width of the body part of the boss, there is an advantage that the coils 70 and 74 inserted in the bosses 6, 92, 94 and 100 can be prevented from coming off. At this time, the difference between the diameter or width of the body part and the diameter or width of the tip part larger than the diameter or width is arbitrary, but for example, it may be about half the diameter of the wire constituting the coil. That's fine.

It is the perspective view which looked at the optical pick-up apparatus provided with the lens holder based on this invention from the optical disk side. It is an external appearance perspective view of the lens holder which concerns on this invention. It is the figure which expressed explicitly the adhesive agent which adhere | attaches the side surface of a lens holder, a tracking coil, and a focusing coil. It is sectional drawing of a lens holder and a metal mold | die at the time of insert-molding a tracking coil and a focusing coil in the lens holder which concerns on this invention. It is a perspective view which shows embodiment which positions the hollow part of a coil using the boss | hub comprised from six cylindrical convex parts. It is a perspective view which shows other embodiment which positions the outer peripheral part of a coil using the boss | hub comprised from six cylindrical-shaped convex parts. It is a perspective view which shows other embodiment which positions the hollow part of a coil using the boss | hub comprised from four cylindrical convex parts. It is a perspective view which shows other embodiment which positions the hollow part of a coil using the boss | hub comprised from two cylindrical convex parts. It is a perspective view which shows other embodiment which positions the hollow part of a coil using the boss | hub comprised from a rectangular parallelepiped convex part. It is a perspective view which shows other embodiment which positions the hollow part of a coil using the boss | hub comprised from the rectangular parallelepiped convex part which removed the four corners. It is a perspective view which shows other embodiment which positions the outer peripheral part of a coil using the boss | hub comprised from the substantially rectangular parallelepiped convex part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical pick-up apparatus 12 Damper base 14 Suspension wire 22 Lens 20 Lens holder 24 Tracking coil 26 Focusing coil 27 Adhesive 28 Lead wire 30 1st magnet 32 2nd magnet 36 Boss 40 1st terminal board 42 2nd terminal Plate 44 Terminal 46 Terminal plate positioning boss 70, 74 Coil 72, 76 Hollow portion 92, 94, 100 Boss

Claims (9)

A lens holder that is used in an optical pickup device that reads information recorded on an optical disc, and has a side surface that is perpendicular to a surface of the optical disc and a tangent to a track of the optical disc,
A lens holder, characterized in that a protruding boss for positioning a winding type tracking coil and / or a winding type focusing coil is provided on the side surface. A lens holder that is used in an optical pickup device that reads information recorded on an optical disc, and has a side surface that is perpendicular to a surface of the optical disc and a tangent to a track of the optical disc,
A lens holder, wherein a winding type tracking coil and / or a winding type focusing coil is bonded to the side surface. The lens holder according to claim 2,
The winding-type tracking coil has a substantially rectangular parallelepiped shape that is long in a direction perpendicular to the surface of the optical disc, and the winding-type focusing coil has a long shape in a direction parallel to the normal line of the track of the optical disc. A lens holder having a rectangular parallelepiped shape. The lens holder according to claim 2 or 3,
A lens holder, wherein a positioning hollow portion is provided at a central portion of the winding tracking coil and / or the winding focusing coil. The lens holder according to claim 4,
The lens holder, wherein the positioning hollow portion is formed in a substantially square shape. The lens holder according to any one of claims 2 to 5,
An end surface of the winding type tracking coil and / or the winding type focusing coil is exposed on a side surface of the lens holder. In the lens holder according to any one of claims 1 to 6,
A lens holder comprising a boss for positioning a central portion of a winding type tracking coil and / or a winding type focusing coil. The lens holder according to claim 7,
The lens holder according to claim 1, wherein the boss is a boss composed of a plurality of convex portions having a substantially cylindrical shape. A method of assembling a lens holder used in an optical pickup device for reading information recorded on an optical disc,
Positioning a winding type tracking coil and / or a winding type focusing coil on a protruding boss on a side surface of the lens holder;
Temporarily bonding the winding type tracking coil and / or the winding type focusing coil to the lens holder;
Fixing the terminal plate to the lens holder;
Connecting lead wires of the winding type tracking coil and / or winding type focusing coil to the terminal plate;
Applying an adhesive to the winding tracking coil and / or winding focusing coil and the lens holder;
Curing the adhesive, and a method of assembling the lens holder.

Images