JP2007305300A - Disk player lens driving device and printed-circuit board coil for the disk player lens driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disk player lens driving device which can avoid the rolling of a movable part of an actuator without making the movable part heavier, and also provide a printed-circuit board coil for the disk player lens driving device. <P>SOLUTION: When focus coils 53 and 63 are fixed to a lens holder 30, the centers of gravity of the focus coils themselves are made lower in the focus direction than the action line of a driving force generated from tracking coils. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lens driving device for a disk player for optically writing or reading information on a disk-shaped recording medium such as a compact disk or an optical disk, and more particularly to improve the rotational moment of a movable part. The present invention relates to a lens driving device for a disc player that eliminates the need for a counterweight.

  2. Description of the Related Art Conventionally, a pickup apparatus 1 that reproduces information recorded on an optical disk such as a CD or a DVD is known. In order to accurately read the information recorded on the optical disc, the pickup device 1 performs focus control for controlling the distance between the information recording surface of the optical disc and the objective lens with respect to warpage or shake of the optical disc, and also the information track of the optical disc. Tracking control for tracking the objective lens with respect to eccentricity is performed. The configuration of the pickup device 1 will be described with reference to FIG.

  The pickup apparatus 1 includes four support wires on a plate-like actuator base 4 having a yoke 3 to which a pair of magnets 2 are fixed, and a support base 5 fixed to a side surface of the actuator base 4 by screws or the like (not shown). A movable part 7 movably supported by 6a to 6d, and an actuator cover 14 formed in a box shape with a metal plate or resin provided with an opening 13 for the objective lens 8 in the top part for protecting the movable part 7; And a pickup body (not shown) that houses optical components such as a light source, a collimator lens, and a beam splitter.

  The movable portion 7 has an objective lens 8 built therein, and faces a lens holder 10 having four fixed arms 9 protruding in the tracking direction, a focus coil 11 wound around the lens holder 10, and the magnet 2. It consists of four D-shaped tracking coils 12 fixed to both side surfaces of the lens holder 10. The movable portion 7 is supported so as to be movable with respect to the actuator base 4 by the four fixed arms 9 of the lens holder 10 being provided on the support base 5 and being fixed to the four support wires 6a to 6d. Is done.

  The four support wires 6a to 6d support the movable portion 7 so as to be movable, and are used as connection lines for supplying a drive current to the focus coil 11 and the four tracking coils 12, so that they are elastic members having good conductivity. It is formed with.

  The focus coil 11 wound around the lens holder 10 has one line end connected to the support wire 6a, for example, and the other line end connected to the support wire 6b. Therefore, the movable portion 7 is driven in the focus direction by supplying the focus drive current to the two support wires 6a and 6b of the support base 5.

  The four tracking coils 12 fixed to the both side surfaces of the lens holder 10 are connected in series by using two support wires 6c and 6d and the wiring member 13. That is, one support wire 6c is connected to one end of two tracking coils 12 fixed and connected in series to one side surface of the lens holder 10, and fixed to the other side surface of the lens holder 10 and connected in series. The other support wire 6d is connected to one end of one tracking coil 12, and the other end of the tracking coil 12 is connected to the other support wire 6c, 6d by connecting the other end of the tracking coil 12 with the wiring member 13. 12 are connected in series. Therefore, the movable portion 7 is driven in the tracking direction by supplying the tracking drive current to the two support wires 6c and 6d.

  By the way, the center of gravity of the lens holder 10 that constitutes the movable portion 7 is positioned substantially at the center of the lens holder 10 even when the focus coil 11 is wound around the trunk as shown in FIG. When the objective lens 8 is built in the lens holder 10, the center of gravity moves to a position indicated by Gn in the drawing near the top surface of the lens holder 10. Further, the center of gravity of the tracking coil 12 fixed to both side surfaces of the lens holder 10 is at the position indicated by Gt in the center of the action line DL connecting the centers of the two tracking coils as shown in FIG. . The center of gravity of the movable portion 7 when the tracking coil 12 is fixed to the side surface of the lens holder 10 is located at a position indicated by Gp in FIG. That is, it is located above the action point of the tracking coil 12.

  The tracking coil 12 generates a driving force around the point of action, but when the center of gravity of the movable part 7 is above the point of action, the movable part 7 generates a rotational moment indicated by M in the figure. In order to solve this problem, a counterweight 15 as shown in FIG. 27D is conventionally attached to the lens holder 10 in order to make the center of gravity of the movable portion 7 coincide with the action point. That is, the moment of rotation is prevented by lowering the position of the center of gravity of the movable portion 7 to the position of the action point by the weight of the counterweight 15.

  As described above, although the counterweight 15 has an effect of suppressing the rotational moment, the total weight of the movable portion 7 is increased by the weight of the counterweight, so that there is a problem that the sensitivity of the actuator is lowered.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a disk player lens driving device and a disk player lens driving device capable of suppressing the generation of a rotational moment without using a counterweight. It is to provide a printed circuit board coil.

  In order to solve the above-described problems, a lens driving device for a disc player according to the present invention includes an objective lens, two drive coil structures disposed at positions facing each other via the objective lens, the objective lens, A movable part having a lens holder, the objective lens, the two drive coil structures, and the lens holder mounted with the two drive coil structures is movably supported, and the two drive coil structures are provided. A disk drive lens driving device having a magnetic flux applying means for applying a magnetic flux to the body, wherein each of the two drive coil structures generates two types of drive coils in different directions. A plane that includes a line of action of a driving force generated by one of the two types of driving coils and is perpendicular to the optical axis of the objective lens Relates to a center of gravity of the two drive coil structure, the center of gravity of the two parts except for the drive coil structure of the movable part, but is characterized by being located opposite one another.

  The direction of the driving force generated by the other of the two types of driving coils may be parallel to the optical axis direction of the objective lens.

  The one drive coil of the two types of drive coils may be a tracking coil, and the other drive coil may be a focus coil.

BEST MODE FOR CARRYING OUT THE INVENTION

  FIG. 1 is a perspective view of a main part of a pickup device 200 according to an embodiment of the present invention. 2 is a plan view of the pickup device 200, and FIG. 3 is a side view of the pickup device 200 when viewed from the spindle motor 180 side. The configuration of the pickup device 200 will be described below with reference to FIGS. 1 to 3.

  The pickup device 200 of the present invention includes four linear elastic members 74, 94, each having a movable portion 130 in which a printed board A coil 50 and a printed board B coil 60 are fixed on both side surfaces of a lens holder 30 incorporating an objective lens 37. The actuator unit 140 is connected to the actuator base 40 by 80 and 104 and supports the movable unit 130 so as to be movable, and an I-shaped N-pole arranged opposite to each other by providing predetermined magnetic spaces on both side surfaces of the movable unit 130. A pair of yokes 152 to which a pair of multi-pole magnets 151 composed of U-shaped S poles are fixed are provided, and the side of the movable portion 130 in the tracking direction (arrow T in the figure) is surrounded. Suspension base 150 having a standing portion 153 disposed opposite to the optical element, and optical components such as a light source, a collimator lens, and a beam splitter (not shown) A semicircular recess 171 formed on a side surface (hereinafter referred to as an arrow “Si” in the drawing, which is referred to as an inner peripheral direction. Also, an outer peripheral direction is referred to as “So”) which is formed by an aluminum die cast to be stored and approaches the spindle motor 180. The pickup body 170 is provided with a pickup body.

  The actuator unit 140 is fixed to the actuator base 150 by inserting a spring-loaded screw and a fixing screw (not shown) into the two mounting holes 41 and 42 of the suspension base 40. The actuator unit 140 is adjusted in posture in the direction indicated by the arrow R1 in FIG. 1 by the V-shaped groove 44 formed on the bottom surface of the suspension base 40 and the M-shaped protruding plate 155 formed on the actuator base 150. Fixed in state. The actuator unit 140 is inserted at one end into a post 173 with a spring fixed to the pickup body 175, and the other end is fixed with a fixing screw 174. The actuator base 150 is fixed in a state in which the posture adjustment in the direction of arrow R2 in the figure is performed by the protrusions 158 formed on the left and right standing portions 153a and 153b and the M-shaped holding portion 172 of the pickup body 170.

  In the pickup device 200 according to the embodiment of the present invention, a semicircular recess 171 is formed on the side surface of the pickup body 170 in the inner circumferential Si direction, thereby making it easy to approach the spindle motor 180 side. Further, as shown in FIG. 2, the pickup device 200 includes an optical center of the objective lens 37 (including the optical axis of the objective lens 37 and perpendicular to the tracking direction) from the linear elastic members 80 and 104 that support the movable portion 130. Distance Ti to the line) is formed smaller than the distance To from the linear elastic members 74 and 94 to the optical center line Oc of the objective lens 37. Thus, by providing the linear elastic members 74 and 94 and the linear elastic members 80 and 104 that support the movable portion 130 at positions asymmetric with respect to the optical center line Oc of the objective lens 37, the objective lens of the pickup device 200 is provided. 37 can further approach the inner peripheral side of the optical disk.

  As described above, in the pickup device 200 according to the embodiment of the present invention, the pickup body 170 is provided with the semicircular recess 171 and the four linear elastic members 74, 94, 80, 104 that support the movable portion 130. Is fixed asymmetrically with respect to the optical center line Oc of the objective lens 37 so that the pickup device 200 is closer to the spindle motor 180 and the inner peripheral side of the optical disk.

  The movable part 130 configured as described above generates a rotational moment. However, the pickup device 200 according to the embodiment of the present invention can be reduced in size without generating a rotational moment by devising the structure of the actuator part 140. Realized light weight. Therefore, the entire structure of the actuator unit 140 used in the pickup device 200 according to the embodiment of the present invention will be described with reference to FIG. 4 and the structure of each member constituting the actuator unit 140 will be described in detail below.

  As shown in FIG. 4, the actuator unit 140 fixes the printed circuit board A coil 50 to the side surface in the front (arrow Sf in the figure) direction of the lens holder 30 including the objective lens 37 and the rear of the lens holder 30 (in the figure). The movable part 130 having the printed circuit board B coil 60 fixed to the side surface in the direction of arrow Sb) is supported by four linear elastic members 74, 80, 94, 104 fixed to the suspension base 40 so as to be movable. ing. The four linear elastic members 74, 80, 94, and 104 constituting the actuator unit 140 are integrally formed by insert molding when the lens holder 30 and the suspension base 40 are resin-molded.

  The lens holder 30 and the suspension base 40 constituting the actuator unit 140 have the structure shown in FIG. 5A is a perspective view of the lens holder 30, and FIG. 5B is a perspective view of the suspension base 40.

  The lens holder 30 is a resin-molded, substantially rectangular member having a hollow structure, and an opening window 32 for the objective lens 37 is formed in the approximate center of the top surface 31, and is the rear Sb side of the lens holder 30 and the top surface. 31 and a pair of fixing arms 34a and 34b, which are elastic member fixing portions protruding horizontally from the bottom surface 33 located in the focus (arrow F in the figure) direction with respect to the top surface 31 in the inner circumferential Si direction; A pair of fixing arms 35a and 35b, which are the other elastic member fixing portions protruding horizontally from the top surface 31 and the bottom surface 33 in the direction of the outer periphery So, on the rear Sb side of the lens holder 30, and on the front Sf side of the lens holder 30 It is formed by a pair of projecting portions 36a and 36b which are terminal fixing portions projecting horizontally from the top surface 31 and the bottom surface 33 in the direction of the outer periphery So.

  On the other hand, the suspension base 40 has two mounting holes 41 and 42 formed to be fixed to the actuator base 150 as shown in FIG. 5B, and four linear elastic members 74 on both sides in the longitudinal direction. 80, 94, and 104 are resin-molded substantially rectangular members having grooves 43a and 43b formed integrally and a V-shaped groove 44 for posture adjustment at the bottom.

  Next, the structure of the printed circuit board A coil 50 and the printed circuit board B coil 60 that are drive coils constituting the movable unit 130 will be described with reference to FIGS. 6 and 7. Since the printed circuit board A coil 50 shown in FIG. 6 is fixed to the front Sf side surface of the lens holder 30, coils and terminals to be described later are formed on the lens holder 30 side. Therefore, in order to make this state easy to understand, the substrate 51 is shown as seen through. That is, the coils and the terminals are formed on the same surface on the back side of the paper. Further, since the printed circuit board B coil 60 shown in FIG. 7 is fixed to the rear Sb side surface of the lens holder 30, the coils and terminals are formed on the same surface in front of the sheet.

  As shown in FIG. 6, the printed circuit board A coil 50 is formed by forming a coil, wiring, etc. on a flat substrate 51 by patterning by copper plating, and includes a tracking A coil 52a, a tracking B coil 52b, and a focus. The A coil 53 and four terminals (a tracking A input terminal 54, a tracking A output terminal 55, a focus A input terminal 56, and a focus A output terminal 57) formed of copper foil are formed on the same surface. The tracking A coil 52a and the tracking B coil 52b are disposed above the substrate 51, and are formed in the same shape symmetrically with respect to the optical axis La. The focus A coil 53 has a coil center on the optical axis La and is formed below the action line DL connecting the coil centers of the tracking A coil 52a and the tracking B coil 52b. Further, since the substrate 51 bears a counterweight of the movable portion 130 described later, a notch portion 58 that is notched upward and a convex portion 59 that is protruded downward are formed.

  Next, a method for connecting the printed circuit board A coil 50 will be described below. The tracking A coil 52a connected to the tracking A input terminal 54 is formed in the counterclockwise direction from the outer periphery to the inner periphery, and is connected to the tracking B coil 52b via a through hole and a copper foil (not shown). The tracking B coil 52 b is formed clockwise from the inner periphery to the outer periphery, and is connected to the tracking A output terminal 55. Accordingly, the tracking A coil 52 a and the tracking B coil 52 b are connected in series between the tracking A input terminal 54 and the tracking A output terminal 55.

  The focus A coil 53 connected to the focus A input terminal 56 is formed clockwise from the outer periphery to the inner periphery, and is connected to the focus A output terminal 57 via a through hole and a copper foil.

  On the other hand, the printed circuit board B coil 60 shown in FIG. 7 is obtained by forming a coil, wiring, etc. by pattern formation by copper plating on a flat substrate 51, similarly to the printed circuit board A coil 50, and a tracking C coil 62a. The tracking D coil 62b, the focus B coil 63, and the four terminals (tracking B input terminal 64, tracking B output terminal 65, focus B input terminal 66, focus B output terminal 67) formed of copper foil are the same. It is formed on the surface. The tracking C coil 62a and the tracking D coil 62b are disposed above the substrate 61, and are formed in the same shape symmetrically with respect to the optical axis La. The focus A coil 63 has a coil center on the optical axis La, and is formed below the action line DL connecting the coil centers of the tracking C coil 62a and the tracking D coil 62b. Similar to the printed circuit board A coil 50, the substrate 61 has a notch 68 cut out at the top and a projection 69 protruding below.

  Next, a method for connecting the printed circuit board B coil 60 will be described below. The tracking C coil 62a connected to the tracking B input terminal 64 is formed in the clockwise direction from the outer periphery to the inner periphery, and is connected to the tracking D coil 62b via a not-shown through hole and copper foil. The tracking D coil 62 b is formed counterclockwise from the inner periphery to the outer periphery, and is connected to the tracking B output terminal 65. Accordingly, the tracking C coil 62 a and the tracking D coil 62 b are connected in series between the tracking B input terminal 64 and the tracking B output terminal 65.

  Further, the focus B coil 63 connected to the focus B input terminal 66 is formed in the clockwise direction from the outer periphery to the inner periphery, and is connected to the focus B output terminal 67 through the through hole and the copper foil.

  Next, the structure of the four linear elastic members 74, 80, 94, 104 that are insert-molded when the lens holder 30 and the suspension base 40 are resin-molded will be described with reference to FIGS. FIG. 8 is a plan view of the upper suspension frame 70 in which two linear elastic members 74 and 80 and respective connecting portions are formed by punching unnecessary portions of a metal flat plate by pressing or the like. FIG. 5 is a plan view of a lower suspension frame 90 in which two linear elastic members 94 and 104 and respective connecting portions are formed by punching unnecessary portions of a metallic flat plate by press working or the like.

  The upper suspension frame 70 is disposed on the top surface 31 side of the lens holder 30 when integrally molded with the lens holder 30 and carries a tracking input terminal 72 and a tracking output terminal 78 described later. Further, the lower suspension frame 90 is disposed on the bottom surface 33 side of the lens holder 30 when integrally molded with the lens holder 30 and serves as a focus input terminal 92 and a focus output terminal 102 described later.

  Since the upper suspension frame 70 and the lower suspension frame 90 have a suspension function and a wiring function for supplying a drive current to the printed circuit board coils 50 and 60, they have elastic force and good conductivity, for example, titanium copper, phosphorus It is formed of metal plates 71 and 91 having a thin plate thickness (for example, about 0.1 mm) such as bronze and beryllium copper. The metal plates 71 and 91 are long hoop materials, and the four linear elastic members 74, 80, 94, and 104, each connection portion, and the like have a plurality of holding members 76 by punching with a mold. And connected to the frame member 77. A plurality of the metal plates 71 and 91 are provided at a predetermined pitch in consideration of productivity.

  As shown in FIG. 8, the upper suspension frame 70 includes a tracking input terminal 72 that is insert-molded on the suspension base 40 and a tracking A input connection portion 73 that is insert-molded on the lens holder 30. ) 74 and the A connecting portion 75, and the holding member 76 holds the frame member 77. Further, a tracking output terminal 78 insert-molded on the upper suspension base 70 and a tracking B output connection portion 79 insert-molded on the lens holder 30 are connected by a linear elastic member (inner circumferential A wire) 80, and the holding member 76. Is held by the frame member 77. A plurality of fixing holes 81 are formed in the frame member 77 of the upper suspension frame 70 in order to accurately fix the frame member 77 to a predetermined position described later.

  On the other hand, as shown in FIG. 9, the lower suspension frame 90 includes a focus input terminal 92 that is insert-molded on the suspension base 40 and a focus A input connection portion 93 that is insert-molded on the lens holder 30. The focus B input connection portion 99 connected to the outer peripheral B wire 94 by the C connection portion 98 is connected to the outer periphery B wire 94 by the D connection portion 100. The focus B output connection unit 101 is connected.

  Further, a focus output terminal 102 insert-molded on the suspension base 40 and a focus B output connection portion 103 insert-molded on the lens holder 30 are connected by a linear elastic member (inner peripheral B wire) 104, and a holding member 96 While being held by the frame member 97, it is connected to the inner circumference B wire 104 by the E connecting portion 105 to the tracking A output connecting portion 106, and the tracking A output connecting portion 106 is connected to the tracking B input connecting portion 108 by the F connecting portion 107. Has been. A plurality of fixing holes 109 are formed in the frame member 97 of the lower suspension frame 90 in the same manner as the upper suspension frame 70.

  The upper suspension frame 70 and the lower suspension frame 90 are formed of metal plates 71 and 91 having the same thickness (H), and an outer peripheral A wire 74 of the upper suspension frame 70 and an outer peripheral B wire 94 of the lower suspension frame 90. Are formed at the same position with respect to the frame members 77 and 97 and at the same plate width (Wo). On the other hand, the inner peripheral B wire 80 of the upper suspension frame 70 and the inner peripheral B wire 104 of the lower suspension frame 90 are formed at the same position with respect to the frame members 77 and 97 and are formed with the same plate width (Wi). ing. Although details will be described later, the plate widths (Wo) of the outer peripheral A wire 74 of the upper suspension frame 70 and the outer peripheral B wire 94 of the lower suspension frame 90 are the same as the inner peripheral B wire 80 of the upper suspension frame 70 and the lower suspension frame 90. The inner peripheral B wire 104 is formed to be narrower than the plate width (Wi). The above is the description of the structure of each member constituting the actuator unit 140.

  Next, the manufacturing method of the actuator part 140 is demonstrated using FIG. 10 thru | or FIG. First, the mold structure and resin molding procedure used when the lens holder 30 and the suspension base 40 are integrally molded using the upper suspension frame 70 and the lower suspension frame 90 will be described with reference to FIG. The mold is formed by integrally forming the resin space between the lens holder 30 and the suspension base 40. FIG. 10 is a structural view of the main part of the mold showing only the lens holder 30 in order to simplify the description. The detailed parts are omitted.

  As shown in FIG. 10, the mold is composed of four molds: a lower fixed mold 110, a pair of left movable mold 111 and right movable mold 112, and an upper movable mold 113, and an injection for injecting resin into the upper movable mold 113. A hole 114 is provided. First, the lower suspension frame 90 is fixed to the mold.

  The lower suspension frame 90 is fixed to a predetermined position of the lower fixed mold 110 of the mold. Since the lower fixed mold 110 is provided with positioning pins (not shown), the lower suspension frame 90 is accurately positioned with respect to the lower fixed mold 110 by inserting the fixing holes 109 of the lower suspension frame 90 into the positioning pins. Positioned. Next, the left movable mold 111 and the right movable mold 112 are placed at predetermined positions on the lower fixed mold 110 with the lower suspension frame 90 interposed therebetween. Next, the upper suspension frame 70 is fixed at predetermined positions of the left movable mold 111 and the right movable mold 112. Like the lower fixed mold 110, the left movable mold 111 or the right movable mold 112 is provided with a positioning pin (not shown). By inserting the fixing hole 81 of the upper suspension frame 70 above the positioning pin, The upper suspension frame 70 is accurately positioned with respect to the left movable mold 111 and the right movable mold 112. Finally, the upper movable mold 113 is placed on the left movable mold 111 and the right movable mold 112 with the upper suspension frame 70 interposed therebetween. Thus, the upper suspension frame 70 and the lower suspension frame 90 are completely housed in the mold, and the resin space 115 for the lens holder 30 is formed so as to surround the upper suspension frame 70 and the lower suspension frame 90. The above is the first step of the manufacturing method.

  Next, the resin space 115 is filled with resin through the injection hole 114. When the resin is cured and the molding of the lens holder 30 and the suspension base 40 is completed, the mold is disassembled in the reverse order of the assembly of the mold. At this time, the left movable mold 111 and the right movable mold 112 are removed by sliding in the left-right direction. The left movable mold 111 and the right movable mold 112 are temporarily fixed while being slid in the left-right direction, and after applying a vibration-damping material made of an ultraviolet curable resin to the grooves 43a and 43b formed on both side surfaces of the suspension base 40 described above. Removed. FIG. 11 shows a state in which the lens holder 30 and the suspension base 40 are integrally formed on the upper suspension frame 70 and the lower suspension frame 90, and a plurality of suspensions are formed in a ladder shape. Unit 120 is completed. The above is the second step of the manufacturing method.

  Next, each terminal part of the printed circuit board A coil 50 and the printed circuit board B coil 60 (hereinafter, referred to as two printed circuit board coils 50 and 60) fixed to the lens holder 30, and four fixed to the lens holder 30. Prior to describing the third step of the manufacturing method for connecting the linear elastic members 74, 80, 94, 104 and the respective connecting portions, adjacent frame members 77, 97 of the upper suspension frame 70 and the lower suspension frame 90. And a step of cutting unnecessary members is provided, which will be described below with reference to FIGS.

  FIG. 12 is a plan view showing the state in which the lens holder 30 and the suspension base 40 are integrally formed with the upper suspension frame 70. The lens holder 30 shows a pair of left and right fixed arms 34a and 35a formed on the top surface 31 side, and a protruding portion 36a. As shown in FIG. 12, the outer periphery A wire 74, the inner periphery A wire 80, and a part of each connecting member are encapsulated in the resin, and the tip of each connection portion is fixed in a state of being exposed from the resin. FIG. 13 is a plan view showing the state in which the lens holder 30 and the suspension base 40 are integrally formed with the lower suspension frame 90. The lens holder 30 shows a pair of left and right fixed arms 34b and 35b formed on the bottom surface 33 side, and a protruding portion 36b. As shown in FIG. 13, a part of the outer peripheral B wire 94, the inner peripheral B wire 104, each connecting member, and the like are included in the resin, and are fixed in a state where the distal end portion of each connection portion is exposed from the resin.

  In the upper suspension frame 70 and the lower suspension frame 90, the lens holder 30 and the suspension base 40 are connected to the four linear elastic members 74, 80, 94, 104 by removing a portion indicated by a dotted frame in the drawing. In this state, the suspension members 120 are obtained by being separated from the frame members 77 and 97.

  As shown in FIG. 12, the upper suspension frame 70 is removed by laser cutting or punching at two locations indicated by dotted line frames a and b in the figure. The outer peripheral A wire 74 integrally formed with the suspension base 40 and connected to the tracking input terminal 72 separated from the frame member 77 is separated from the frame member 77 and fixed to the fixed arm 35a of the lens holder 30, and the A connection The tracking A input connecting portion 73 connected by the member 75 is fixed to the protruding portion 36 a in a state where it is exposed on the front side surface of the lens holder 30. On the other hand, the inner peripheral A wire 80 integrally formed with the suspension base 40 and connected to the tracking output terminal 76 separated from the frame member 77 is separated from the frame member 77 and fixed to the fixed arm 34 a of the lens holder 30. The tracking B output connecting portion 79 connected to the inner circumferential A wire 80 is fixed in a state of being exposed on the rear side surface of the lens holder 30.

  Further, in the lower suspension frame 90, as shown in FIG. 13, the five portions indicated by the dotted line frame c in the figure are removed by the same method. The outer peripheral B wire 94 integrally formed with the suspension base 40 and connected to the focus input terminal 92 separated from the frame member 97 is separated from the frame member 77 and fixed to the fixed arm 35b of the lens holder 30, and the B connecting member. The focus A input connecting portion 93 connected at 95 is fixed to the protruding portion 36 b in a state where it is exposed on the front side surface of the lens holder 30. Further, the focus B input connection portion 99 cut off from the outer periphery B wire 94 is fixed in a state where it is exposed on the rear side surface of the lens holder 30 and is connected to the focus B input connection portion 99 and the D connection portion 100. The B output connection portion 101 is fixed in a state of being exposed on the front side surface of the lens holder 30.

  The inner peripheral B wire 104 integrally formed with the suspension base 40 and connected to the focus output terminal 102 separated from the frame member 97 is separated from the frame member 77 and fixed to the fixing arm 34b of the lens holder 30, The focus B output connection portion 103 connected to the inner peripheral B wire 104 is fixed in a state of being exposed on the rear side surface of the lens holder 30. Further, the tracking B input connecting portion 108 separated from the frame member 97 is fixed in a state where it is exposed on the rear side surface of the lens holder 30, and the tracking A output connected to the tracking B input connecting portion 108 and the F connecting portion 107. The connecting portion 106 is fixed in a state exposed on the front side surface of the lens holder 30.

Next, a method for connecting the lens holder 30 and the two printed circuit board coils 50 and 60, which is the third step of the manufacturing method described above, will be described with reference to FIG. In FIG. 14, the printed circuit board A coil 50 and the printed circuit board B coil 60 are arranged at positions away from both side surfaces of the lens holder 30 in order to make the structure of the soldered portion easier to understand. Each of the integrally formed connecting portions is schematically extended (portion indicated by a dotted line in the figure).
Each connection portion of the lens holder 30 including the objective lens 37 is connected to the printed board A coil 50 and the printed board B coil 60 in a state where the printed board A coil 50 and the printed board B coil 60 are fixed at predetermined positions of the lens holder 30. It forms in the positional relationship which contacts each terminal formed.

  Specifically, as shown in FIG. 14, the four terminal portions (tracking A input terminal portion 54, tracking A output terminal portion 55, focus A input terminal portion 56, focus A output terminal 57) of the printed circuit board A coil 50 are The four connection portions (tracking A input connection portion 73, focus A input connection portion 93, focus B) formed to be exposed on the front side surface of the lens holder 30 while being fixed at a predetermined position on the front side surface of the lens holder 30. The output connection portion 101 and the tracking A output connection portion 106) are in contact with each other. Also, the four terminal portions (tracking B input terminal 64, tracking B output terminal 65, focus B input terminal 66, focus B output terminal 67) of the printed circuit board B coil 60 are exposed on the rear side surface of the lens holder 30. The four contact portions (the tracking B output connection portion 79, the focus B input connection portion 99, the focus B output connection portion 103, and the tracking B input connection portion 108) are in contact with each other. Therefore, the actuator part 140 is formed by soldering them.

  The outer peripheral A wire 74 connected to the tracking input terminal 72 is connected to the tracking A input terminal portion 54 via the A connecting portion 75, and the tracking A input terminal portion 54 is the tracking A input terminal of the printed circuit board A coil 50. Soldered to the part 54. Further, the tracking A output terminal portion 55 of the printed circuit board A coil 50 is soldered to the tracking A output connection portion 106 of the lens holder 30 and is also connected to the tracking A output connection portion 106 and the F connecting portion 107. The tracking B input connection portion 108 of the holder 30 is soldered to the tracking B input terminal 64 of the printed circuit board B coil 60. Further, the inner circumference A wire 80 connected to the tracking output terminal 78 is connected to the tracking B output connection portion 79, and the tracking B output connection portion 79 is soldered to the tracking B output terminal 65 of the printed circuit board B coil 60. Is done.

  As described above, the tracking A coil 52 a and the tracking B coil 52 b of the printed circuit board A coil 50 are connected in series between the tracking A input terminal portion 54 and the tracking A output terminal portion 55, and Since the tracking C coil 62a and the tracking D coil 62b are connected in series between the tracking B input terminal 64 and the tracking B output terminal 65, there are four tracking coils between the tracking input terminal 72 and the tracking output terminal 78. 52a, 52b, 62a, 62b are connected in series.

  On the other hand, the outer peripheral B wire 94 connected to the focus input terminal 92 is connected to the focus A input terminal portion 93 via the B connecting portion 95, and the focus A input terminal portion 93 is connected to the focus A of the printed circuit board A coil 50. It is soldered to the input terminal 56. The focus A output terminal portion 57 of the printed circuit board A coil 50 is soldered to the focus A output connection portion 101 of the lens holder 30 and is connected to the tracking A output connection portion 101 and the C connection portion 100. The focus B input connection portion 99 of the holder 30 is soldered to the focus B input terminal 66 of the printed circuit board B coil 60. Further, the inner peripheral B wire 104 connected to the focus output terminal 102 is connected to the focus B output connection portion 103, and the focus B output connection portion 103 is soldered to the focus B output terminal 67 of the printed circuit board B coil 60. Is done.

  As described above, the focus A coil 53 of the printed circuit board A coil 50 is connected between the focus A input terminal portion 56 and the focus A output terminal portion 57, and the focus B coil 63 of the printed circuit board B coil 60 is connected to the focus B coil. Since it is connected between the input terminal 66 and the focus B output terminal 67, the focus A coil 53 and the focus B coil 63 are connected in series between the focus input terminal 94 and the focus output terminal 104. The above is the third step of the manufacturing method.

  As described above, the actuator unit 140 used in the pickup device 200 according to the embodiment of the present invention integrally forms the four linear elastic members 74, 80, 94, 104 with the lens holder 30 and the actuator base 40. In addition, it is not necessary to connect the outside using the wiring material by integrally forming the connecting portions that connect the printed board A coil 50 and the printed board B coil 60. Therefore, the operation process is simplified and the highly reliable actuator unit 140 is obtained.

  Next, a procedure for incorporating the actuator unit 140 into the suspension base 150 will be described with reference to FIG. 15A is a perspective view of the actuator portion 140, FIG. 15B is a perspective view of the stopper member 157, and FIG. 15C is a perspective view of the actuator base 150. FIG.

  As described above, the actuator portion 140 is fixed after placing the V-shaped groove 44 of the actuator base 40 on the two M-shaped projecting plates 155 of the suspension base 150 and adjusting the posture with the spring-loaded screw 45 and the fixed screw 46. Thereby, the movable part 130 is supported so as to be movable in a state where a predetermined magnetic space is formed with respect to the pair of magnets 151. Thereafter, the stopper member 157 is inserted into the insertion hole 154 of the pair of standing portions 153 provided on the suspension base 150 so as to surround the movable portion 130.

  As shown in FIG. 15B, the stopper member 157 is a linear member that is bent in a substantially U shape as a whole, and the U-shaped tip is further on the inner side of the standing portion 153, that is, on the movable portion 130 side. Protruding stop portions 158a and 158b are provided. When the stopper member 157 is inserted into the insertion hole 154 of the standing portion 153, the distal ends of both the restraining portions 158a and 158b are inserted from the outside of the standing portion 153, so that the stopper member 157 is formed of an elastic member having a spring effect. .

  The actuator unit 140 mounted on the suspension base 150 has a pair of upright portions 153 provided so as to surround the movable unit 130, and the movement range in the tracking direction of the movable unit 130 is restricted. The stopper member 157 moves the movable unit 130. The movement range in the focus direction is restricted.

  Specifically, this will be described with reference to FIG. 16A is a plan view showing the positional relationship between the actuator portion 140, the standing portion 153 of the suspension base 150, and the stopper member 157, and FIG. 16B is a lens holder in which the objective lens 37 is built. 30 is a side view showing a positional relationship among 30, the standing portion 153, and the stopper member 157. FIG.

  As shown in FIG. 16, when the stopper member 157 is inserted into the insertion hole 154 of the standing portion 153, one of the stop portions 158 a of the stopper member 157 is fixed to the lens holder 30 so as to be separated from the focus direction. The other restraining portion 158b of the stopper member 157 is disposed substantially at the center of the other fixed arm 35a, 35b formed spaced apart from the lens holder 30 in the focus direction. Accordingly, when the movable portion 130 is driven in the upward focus direction, the movable portion 130 moves within a distance M2 until the left and right fixed arms 34b and 35b formed on the bottom surface 33 side of the lens holder 30 come into contact with the stop portions 158a and 158b. Is regulated. Further, when driven in the downward focus direction, the movement range is restricted by the distance M1 until the left and right fixed arms 34a, 35a formed on the top surface 31 side of the lens holder 30 come into contact with the stop portions 158a, 158b. The As described above, since the fixed arms 35a and 35b, which are fixed portions of the elastic member, are used as a mechanism for restricting the movement range in the focus direction, cost reduction is realized.

  The insertion hole 154 formed in the standing portion 153 may be provided with a pair of insertion holes 156a and 156b in which a plurality of insertion positions are formed as shown in FIG. By configuring in this way, it becomes possible to define the moving range of the movable unit 130 differently from the moving range in the downward direction, and the versatility of the suspension base 150 is increased.

  As described above, after the actuator part 140 is fixed to the suspension base 150, the stopper member 157 is inserted into the insertion hole 154 of the standing part 153. Then, by fixing the suspension base 150 to the pickup body 170, the pickup device 200 according to the embodiment of the present invention is completed.

  As described above, in the movable unit 130 constituting the pickup device 200 according to the embodiment of the present invention, the moving range in the tracking direction is restricted by the standing portion 153 of the suspension base 150, and in the focus direction by the stopper member 157. The movement range is regulated. Therefore, the pickup device 200 according to the embodiment of the present invention does not require an actuator cover, and can be reduced in size and weight.

  Next, the configuration of the four linear elastic members 74, 94, 80, and 104 that support the movable portion 130 and the action of preventing the movable portion 130 from rolling will be described with reference to FIGS.

  Although the movable part 130 is actually supported by four linear elastic members 74, 94, 80, 104, only the outer peripheral A wire 74 and the inner peripheral A wire 80 are used in order to avoid complicated explanation. It is shown in the figure. This makes no difference in operation. FIG. 18 is a plan view of the actuator unit 140, and FIG. 19 is a schematic diagram illustrating the rotational moment of the movable unit 130.

  As described above, the pickup apparatus 200 according to the embodiment of the present invention uses the distance Ti from the inner peripheral A wire 80 supporting the movable portion 130 to the optical center line Oc of the objective lens 37 as shown in FIG. It is formed smaller than the distance To from the wire 74 to the optical center line Oc of the objective lens 37. Accordingly, the inner circumference A wire 80 and the outer circumference A wire 74 are formed with the same plate thickness H, but the plate width Wi of the inner circumference A wire 80 is larger than the plate thickness Wo of the outer circumference A wire 74 ( Wi> Wo).

For this reason, the spring constant Ki of the inner periphery A wire 80 is shown by following Formula (1).
Ki∝Ti ³ H (1)

Similarly, the spring constant Ko of the outer periphery A wire 74 is expressed by the following equation (2).
Ko∝To ³ H (2)

  Therefore, the spring constant Ki of the inner peripheral A wire 80 is larger than the spring constant Ko of the outer peripheral A wire 74 (Ki> Ko) from the relationship of Wi> Wo described above.

Further, if the amount of deflection in the focus direction of the inner peripheral A wire 80 and the outer peripheral A wire 74 when the movable portion 130 is displaced in the focus direction by the driving force Fd is x, the movable portion as shown in FIG. When 130 is displaced in the focus direction, the restoring force Fi of the inner circumferential A wire 80 is expressed by the following equation (3).
Fi = Kix (3)

Similarly, the restoring force Fo of the outer periphery A wire 74 is represented by the following formula (4).
Fo = Kox (4)

  From the relationship of Ki> Ko described above, the restoring force Fi of the inner circumferential A wire 80 is larger than the restoring force Fo of the outer circumferential A wire 74 (Fi> Fo).

  The rotational moment of the movable part 130 is determined from the center of gravity Gt of the movable part 130 (the point of action of the focus driving force and the center of gravity of the movable part 130 coincide with each other on the optical axis La) to the spring (inner circumference A wire 80 and outer circumference. It is obtained by the product of the distance to the A wire 74) and the restoring force at the position where the spring (the inner peripheral A wire 80 and the outer peripheral A wire 74) is fixed. Therefore, if the rotational moment of the restoring force Fi of the inner peripheral A wire 80 and the rotational moment of the restoring force Fo of the outer peripheral A wire 74 are balanced, the rotational moment becomes 0 and the movable portion 130 does not rotate.

From the above, the plate width Wi of the inner peripheral A wire 80 and the plate width Wo of the outer peripheral A wire 74 are set to the relationship shown by the following equation (4).
FiTi = FoTo (4)

  As described above, in the pickup device 200 according to the embodiment of the present invention, the distance Ti from the inner peripheral A wires 80 and 104 supporting the movable portion 130 to the optical center line Oc of the objective lens 37 is set as the outer peripheral A wire 74. , 94 to be smaller than the distance To from the optical center line Oc of the objective lens 37, and the plate width Wi of the inner peripheral A wires 80, 104 is formed to be larger than the plate thickness Wo of the outer peripheral A wires 74, 94. Thus, the inner circumference side of the actuator part 140, that is, the spindle motor 180 side is made smaller than the outer circumference side without causing rolling due to the rotational moment of the movable part 130, and the objective lens is brought closer to the inner circumference side of the optical disk. It becomes possible to make it.

  The setting for making the spring coefficients of the linear elastic members 74, 94, 80, 104 different in this way is not limited to the inner peripheral side and the outer peripheral side, but the linear elastic members 74, 80 on the upper side in the focusing direction and the lower side It is also possible to vary the spring constant between the linear elastic members 94 and 104. That is, as shown in FIG. 20, the distance To from the center of gravity Gt of the movable body 130 to the upper linear elastic members 74 and 80 and the distance To from the lower linear elastic members 94 and 104 are different. When the center of gravity Gt is driven in the tracking direction with Ft, the springs of the upper linear elastic members 74 and 80 are satisfied so that the above-described formula (4) is satisfied in order to suppress the generation of the rotational moment due to the restoring force of the spring. The constants and the spring constants of the lower linear elastic members 94 and 104 may be set as appropriate.

  In addition, the spring constant is not necessarily established by the above equation (4), and the spring constant is changed so that the rotational moment applied to the movable body is reduced as compared with the case where the spring constants are all equal. Can be set to contribute to deter rolling.

  Next, the center of gravity of the movable part 130 will be described with reference to FIGS. Note that the printed circuit board A coil 50 and the printed circuit board coil 60 are actually fixed to the movable unit 130, but the printed circuit board A coil 50 and the substrates 51 and 61 of the printed circuit board coil 60 are formed in the same shape. Can be considered the same weight position. Therefore, in order to avoid complicated explanation, FIGS. 21 to 24 show only the printed circuit board A coil 50. 21 is a view showing the center of gravity when the objective lens 37 is built in the lens holder 30, FIG. 22 is a view showing the center of gravity of the printed circuit board coil 50, and FIG. FIG. FIG. 24 shows an example in which the focus A coil 53 is provided further downward.

  Since the lens holder 30 is a substantially square member having a resin-molded hollow structure and has a top surface 31, the center of gravity of the lens holder 30 is the center of the lens holder 30 as shown in FIG. It is in the position of Gb in the figure closer to the top surface 31 than. When the objective lens 37 is built in the lens holder 30, the center of gravity of the lens holder 30 moves to a position indicated by Gn in the figure further moved to the top surface 31 side.

  On the other hand, the printed circuit board coil 50 is formed in a region between the tracking A coil 52a and the tracking B coil 52b as shown in FIG. A portion 59 is formed. The printed circuit board A coil 50 is formed with a tracking A coil 52a and a tracking B coil 52b symmetrically with respect to the optical axis La. Accordingly, the center of gravity of the tracking A coil 52a and the tracking B coil 52b is located at the position indicated by Gt in the figure which is the intersection of the tracking driving force action line DL and the optical axis La connecting the center points of the two tracking coils 52a and 52b. . The center of gravity of the focus A coil 53 is at a position indicated by Gf in the figure that intersects the optical axis La at the center of the focus A coil 53. From the above, the center of gravity of the printed circuit board coil 50 is at a position indicated by Gp in the drawing below the center of gravity Gt of the two tracking coils 52a and 52b and above the center of gravity Gf of the focus A coil 53.

  FIG. 23 shows a state in which the printed circuit board A coil 50 is fixed to the lens holder 37. When the printed circuit board A coil 50 is fixed at a position where the top surface 31 of the lens holder 30 and the top surface of the substrate 51 are straight, the convex portion 59 of the printed circuit board A coil 50 is below the bottom surface 33 of the lens holder 30. Fixed in a protruding state.

  In a state where the printed circuit board coil 50 is fixed to the lens holder 37 having the objective lens 37, the distance N1 from the center of gravity Gn of the lens holder 30 having the objective lens 37 to the action line DL of the tracking driving force, and the printed circuit board coil 50. If the distance N2 from the center of gravity Gp to the action line DL of the tracking driving force is equal, the center of gravity Gm of the movable part 130 is formed on the optical axis La of the objective lens 37 and on the action line DL of the tracking driving force. .

  Therefore, when the printed circuit board A coil 50 is designed, the line connecting the center point Gn of the tracking coils 52a and 52b from the center of gravity Gn of the lens holder 30 incorporating the objective lens 37, that is, the action line of the tracking driving force. By setting the size of the notch portion 58 and the size of the convex portion 59 so that the distance N1 to the DL and the distance N2 from the center of gravity Gp of the printed circuit board coil 50 to the action line DL are equal, The center of gravity can be set at the intersection of the tracking driving force action line DL and the optical axis La, and no rotational moment can be generated when the movable unit 130 is driven in the tracking direction. As described above, in this embodiment, the weight of the focus coil 53 can be used as a counterweight. Therefore, the movable portion 130 is not increased in weight as compared with the case where a dedicated counterweight is used, and an adverse effect due to the rotational moment is exerted. It can be avoided.

  The notch 58 formed above the substrate 51 lightens the center of gravity of the printed circuit board A coil 50, and the distance between the action line DL of the two tracking coils 52a and 52b and the center of gravity Gp of the printed circuit board A coil 50, That is, N2 can be increased. This further increases the weight effect as a counterweight. That is, by providing the cutout portion 58 in the substrate 51, the weight as the counterweight can be substantially increased without increasing the total weight of the movable portion 130. Thereby, the margin with respect to the weight of the objective lens 37 increases, and versatility improves.

  Further, the printed circuit board A coil 50 may be configured such that the focus A coil 53 is positioned further downward as shown in FIG. With this configuration, the center of gravity Gf of the focus A coil 53 is positioned below the example shown in FIG. 22, and therefore the center of gravity Gp of the printed circuit board A coil 50 also moves downward. However, in such a configuration, the weight of the substrate 51 becomes larger than that of the example shown in FIG. 22, and the convex portion 59 of the substrate 51 becomes large, thereby limiting the range of movement of the movable portion 130 in the downward focus direction. become. Therefore, the shape of the printed circuit board A coil 50 is set according to the position of the center of gravity of the lens holder 30 incorporating the objective lens 37.

  Next, the operation of the movable part of the pickup device 200 according to the embodiment of the present invention will be described with reference to FIG. FIG. 25 is an explanatory diagram showing the relative positional relationship between the printed circuit board A coil 50 and the magnet 151 when the movable portion 130 is in the normal position.

The magnet 151 is a multipolar magnetized magnet in which, for example, an N pole is magnetized in a substantially square shape at the center, and an approximately U-shaped S pole is magnetized so as to surround the N pole from three directions. The N-pole magnetized region emits a magnetic flux perpendicular to the paper surface in the drawing and directed from the back side to the front side. As shown in FIG. 25, the center of each coil formed on the printed circuit board A coil 50 is arranged on the boundary line between the N pole and the S pole of the magnet 151.
When a tracking drive current is supplied between the tracking input terminal 54 and the tracking output terminal 55 and a current in the direction indicated by the arrow in the figure flows through the tracking A coil 52a and the tracking B coil 52b, the leftward direction indicated by the arrow T in the figure. Tracking driving force is generated. Further, when a driving current opposite to this is supplied, a tracking driving force in the right direction opposite to the arrow T in the figure is generated.

On the other hand, when a focus drive current is supplied to the focus input terminal 56 and the focus output terminal 57 and a current in the direction shown in the figure flows through the focus coil 53, an upward focus drive force indicated by an arrow F in the figure is generated. Similarly, when a drive current opposite to this is supplied, a downward focus drive force opposite to the arrow F in the figure is generated.
[The invention's effect]

  According to the present invention, it is possible to provide a lens drive device for a disc player and a printed circuit board coil for the lens drive device that can avoid rolling of the movable portion without increasing the weight of the movable portion of the actuator.

1 is a perspective view of a pickup device according to an embodiment of the present invention. The top view of the pick-up apparatus of embodiment of this invention. The side view of the inner peripheral side of the pickup apparatus of the embodiment of the present invention. The perspective view of the actuator part which comprises a pick-up apparatus. The perspective view of the lens holder and actuator base which comprise a movable part. The structural diagram of the printed circuit board A coil which comprises a movable part. The structural diagram of the printed circuit board B coil which comprises a movable part. FIG. 6 is a structural diagram of an upper suspension frame used for a movable part. FIG. 4 is a structural diagram of a lower suspension frame used for a movable part. The principal part structure figure of the metal mold | die when shape | molding a suspension unit. The perspective view which shows the delivery form of a suspension unit. The figure which shows the cut part of the upper suspension frame by which the lens holder and the suspension base were integrally molded. The figure which shows the cut part of the lower suspension frame by which the lens holder and the suspension base were integrally molded. The structure perspective view when connecting a printed circuit board coil to a suspension unit. The figure which showed the procedure which incorporates an actuator part in a suspension base. The figure used when demonstrating the function of a stopper member. The figure which shows other embodiment of a stopper member. The figure used to explain suppression of rotational moment. The figure used to explain suppression of rotational moment. The figure used to explain suppression of rotational moment. The figure used when demonstrating the relationship between a printed circuit board coil and a counterweight. The figure used when demonstrating the relationship between a printed circuit board coil and a counterweight. The figure used when demonstrating the relationship between a printed circuit board coil and a counterweight. The figure which shows another form of a printed circuit board coil. The figure used when explaining the driving force of focus and tracking. The figure which shows the structure of the conventional pick-up apparatus. The figure explaining the problem of the conventional pick-up apparatus.

Explanation of symbols

30 ... lens holder 37 ... objective lens 40 ... actuator base 50, 60 ... printed circuit board coil 74, 94, 80, 104 ... linear elastic member 130 ... movable part 140 ... Actuator 150 ... Suspension base 151 ... Magnet 153 ... Erecting portion 154 ... Insertion hole 157 ... Stopper member 200 ... Lens driving device for disc player

Claims (3)

An objective lens;
Two drive coil structures disposed at positions facing each other via the objective lens;
A lens holder on which the objective lens and the two drive coil structures are mounted;
Magnetic flux applying means for movably supporting a movable part having the objective lens, the two drive coil structures, and the lens holder, and for applying a magnetic flux to the two drive coil structures. A lens drive device for a disc player comprising:
Each of the two drive coil structures has two types of drive coils that generate drive force in different directions,
The center of gravity of the two drive coil structures and the movable part with respect to a plane that includes a line of action of a drive force generated by one of the two types of drive coils and is perpendicular to the optical axis of the objective lens And a center of gravity of a portion excluding the two drive coil structures is located on the opposite side.   2. The lens driving device according to claim 1, wherein the direction of the driving force generated by the other driving coil of the two types of driving coils is parallel to the optical axis direction of the objective lens.   2. The lens driving device for a disc player according to claim 1, wherein one of the two types of driving coils is a tracking coil, and the other driving coil is a focus coil.

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