JP4229818B2 - Optical head device - Google Patents

Description

  The present invention relates to an optical head device configured by attaching an objective lens driving device in which a lens holder to which an objective lens is mounted is elastically supported so as to be displaceable by a plurality of support wires to an optical housing in which various optical elements are incorporated. In particular, the present invention relates to an optical head device in which a support plate on which one end of a plurality of support wires is supported and fixed by soldering is connected to a main printed circuit board to which a transmission cable is connected.

  2. Description of the Related Art An optical head device that optically reads or writes signals on a signal recording medium such as a disk is generally configured by attaching an objective lens driving device to an optical housing in which various optical elements other than the objective lens are incorporated. . In the objective lens driving device, a system in which a lens holder to which the objective lens is mounted is elastically supported so as to be displaceable with respect to the actuator base by two or three support wires on each of the left and right sides is mainstream. It has become.

  In such an objective lens driving device, driving coils such as a focusing coil and a tracking coil are mounted on a lens holder, and effective coil sides of these driving coils are arranged in an effective magnetic flux formed by a magnetic circuit. Thus, the objective lens is driven in the focus direction, the tracking direction, and the like according to the drive signal supplied to the drive coil.

By the way, in an objective lens driving apparatus configured to support a lens holder with a plurality of support wires, the objective lens is usually driven by supplying a drive signal to each drive coil via a predetermined support wire. Each end of each support wire is supported and fixed by soldering to a support plate composed of a printed board fixed to the actuator base. Then, the optical head device connects a flexible substrate serving as a transmission cable to the support plate, whereby a circuit board on the apparatus main body side on which the optical head device is mounted via the flexible substrate, and each driving coil mounted on the lens holder, Is connected. (See Patent Document 1)
In addition to the drive coil, the optical head device includes a semiconductor laser as a light source, a photodetector for obtaining various received light signals for generating a read signal, a focus error signal, and a tracking error signal from a recording medium, and a circuit of the main device. Since it is necessary to electrically connect to the board, the flexible board connected to each electrical component of these optical head devices is connected to the main printed board fixed to the optical housing, and the main printed board and the device main body side are connected. By connecting the circuit board to the circuit board on the device body side via the main printed circuit board, each electrical component of the optical head device such as the drive coil, semiconductor laser and photodetector is connected by the transmission cable. Has been done. In this way, when the optical head device and the circuit board on the apparatus main body side are electrically connected via the main printed board, a connector in which the connection terminal portion of the transmission cable is inserted into the main printed board is often used. (See Patent Document 2)
Utility Model Registration No. 2529433 Utility Model Registration No. 2570205

One end of a plurality of support wires is supported and fixed by soldering to a support plate composed of a printed circuit board fixed to the actuator base, and flexible to connect this support plate and the main printed circuit board Using a transmission cable such as a substrate is disadvantageous in terms of the number of parts and workability.

  In addition, in order to simplify the connection work between the electrical components of the optical head device and the main printed circuit board, or to reduce the number of parts, the semiconductor laser can be directly connected to the main printed circuit board. There is a case where a land for soldering the lead terminal is formed. In such a case, the displacement is caused by the displacement of the transmission cable connected to the circuit board on the apparatus body side with the movement of the optical head device by thread feeding. As a result, the force generated along with this is applied to the main printed circuit board, causing vibrations to the semiconductor laser.

According to the first aspect of the present invention, a main printed circuit board, which is attached to an optical housing and connected to a circuit board of an apparatus main body on which an optical head device is mounted, a transmission cable for transmitting and receiving electrical signals, and a plurality of support wires each one end is supported and fixed by soldering, and a by PCB configured support plate fixed to the actuator base, Ru joint portion to be jointed to the main printed circuit board to the support plate is formed integrally together with the plurality of wiring patterns connected to the one end of each of the support wires are formed, the engaging portion and the engaged portion to be engaged with one another to either one and the other of the main printed circuit board and the joint portion is formed, the land portions to be soldered to each other in the engaging portion and the engaged portion is formed, Tracking the main printed circuit board Installed on the surface of the optical housing substantially orthogonal to the mounting direction, in a positional relationship arranged substantially orthogonal to the support plate, and by soldering the engagement portion and the engagement portion, the main printed circuit board, In addition, a projecting piece of the optical housing is inserted into a notch formed in the main printed circuit board to be installed in the optical housing, and further, a lead terminal of a semiconductor laser is soldered to the main printed circuit board. A through groove is formed in a part leaving a coupling portion so as to surround the laser region of the main printed circuit board to which the lead terminal is connected, and the connection region in which the connection portion of the transmission region of the laser region and the main printed circuit board is disposed Are separated across the through groove .

  The optical head device of the present invention integrally forms a joint portion in which a wiring pattern joined to the main printed circuit board is formed on a support plate that is supported and fixed by soldering at each end of a plurality of support wires, Since this joint is engaged with the main printed circuit board, there is no need to use a transmission cable such as a flexible circuit board to connect the support plate and the main printed circuit board, and the number of parts can be reduced and work can be done. Can be improved.

  In this case, the main printed circuit board and the support plate are positioned so as to be substantially orthogonal to each other, and the engaging portion of the main printed circuit board and the engaged portion of the joint portion of the supporting plate are connected to the engaging portion and the engaged portion. The main printed circuit board and the support plate can be easily connected by soldering each land portion formed in the engaging portion and the engaged portion so as to intersect each other in the thickness direction by a slit formed in one of the two.

In particular , the optical head device of the present invention forms a through groove so as to surround a laser region of a main printed circuit board to which a lead terminal of a semiconductor laser is connected, leaving a coupling part in part, and the laser region and the main printed circuit board Since the connection area where the connection portion of the transmission cable connected to the circuit board on the device main body side is disposed is separated by sandwiching the through groove, the transmission cable is displaced as the optical head device moves. As a result, the vibration applied to the main printed circuit board with this displacement is divided by the through groove, and the influence of the vibration on the semiconductor laser can be greatly reduced.

  FIG. 1 is a perspective view showing a completed state of the optical head device according to the present invention, and FIG. 2 is a partially developed perspective view showing a state during the assembly of the optical head device shown in FIG.

  In these drawings, reference numeral 1 denotes an objective lens driving device for driving the objective lens 2, 3 denotes an optical housing in which various optical elements other than the objective lens 2 are incorporated, and the optical head device is provided in the optical housing 3 with the objective lens driving device 1. It is configured with an attached.

  The objective lens driving device 1 is configured such that a lens holder 4 to which an objective lens 2 is mounted is elastically supported so as to be displaceable with respect to the actuator base 6 by a total of four support wires 5 on each of the left and right sides. Each support wire 5 is soldered and fixed to a support plate 7 whose one end is fixed to the actuator base 6, and each other end protrudes to the left and right sides of the lens holder 4. It is adhesively fixed to 4a.

  In this case, the support wires 5 are arranged in parallel on top of each other with two upper and lower wires arranged on both sides of the lens holder 4 with the objective lens 2 in between.

  The lens holder 4 is provided with a focus coil and a tracking coil, and the effective coil sides of the focus coil and the tracking coil are connected to an effective magnetic flux. A magnetic circuit is formed on the actuator base 6 so as to be disposed inside.

  Therefore, by supplying a focus error signal to the focus coil, the objective lens 2 is driven together with the lens holder 4 so that the focus control is performed to focus the light beam on the signal surface of the recording medium such as a disk, and the tracking coil By supplying the tracking error signal, the objective lens 2 is driven together with the lens holder 4 so as to perform tracking control for causing the light beam to follow the signal track of the recording medium.

  By the way, the support plate 7 to which one end of each of the four support wires 5 is fixed by soldering is constituted by a printed circuit board. The support plate 7 has transmission paths corresponding to the positive and negative polarities of the focus error signal and the tracking error signal. Wiring patterns 8a to 8d are formed, and one end of each support wire 5 is connected to a predetermined one of the corresponding wiring patterns 8a to 8d by soldering and fixing to the support plate 7, respectively.

  The four support wires 5 are connected to the winding start ends and the winding end ends of the focus coil and the tracking coil one by one on the other end side. Therefore, by supplying a focus error signal and a tracking error signal with positive and negative polarities to the wiring patterns 8a to 8d of the support plate 7, the focus error signal and the tracking error signal are supplied to the focus coil and the tracking coil of the lens holder 4, respectively. I can do it.

  By the way, a main printed circuit board 11 on which a connector 10 to which a circuit board (not shown) of an apparatus main body on which an optical head device is mounted and a transmission cable 9 for exchanging electrical signals is connected is installed in the optical housing 3. Is attached and fixed to the side surface of the optical housing 3 substantially perpendicular to the tracking direction.

Lead terminals 12 a to 12 c of a laser diode 12 are soldered to the main printed circuit board 11. In FIG. 2, the laser diode 12 is shown as being installed on the main printed circuit board 11 before the main printed circuit board 11 is attached to the optical housing 3 for convenience. In this state, the lead terminals 12a to 12c of the laser diode 12 are projected from the holes of the main printed board 11, and the main printed board 11 is disposed in the optical housing 3 as shown in FIG. In this case, the protrusion 13a of the optical housing 3 is inserted into the notch 20 formed in the main printed circuit board 11, and the main printed circuit board 11 is positioned so as to be sandwiched between the hook-shaped protrusions 13b formed in the optical housing 3. Then, the main printed circuit board 11 is installed in the optical housing 3.

  Further, since the joint portion 14 joined to the main printed circuit board 11 is integrally formed on the support plate 7, the engaging portion 14 a at the tip of the joint section 14 is formed on the main printed circuit board 11. It is inserted and engaged with the slit 15 serving as an engaging portion so as to be sandwiched by intersecting in the thickness direction.

  When the main printed circuit board 11 is installed in the optical housing 3 in this way, the main printed circuit board 11 is fixed to the optical housing 3 by screws.

  In a state where the main printed circuit board 11 is fixed to the optical housing 3, the lands 16 a to 16 d formed in the engaging portion 14 a of the joint portion 14 and the lands 17 a to 17 formed adjacent to the slit 15 of the main printed circuit board 11. The main printed circuit board 11 and the support plate 7 are connected to each other by soldering 17d corresponding to each other.

  With this connection, the circuit board of the device main body and the support plate 7 are electrically connected via the transmission cable 9 connected to the connector 10, and the focus error signal supplied from the circuit board of the device main body via the transmission cable 9. The tracking error signal is supplied to the focus coil and the tracking coil via the main printed board 11 and the support plate 7, respectively.

  By the way, the optical head device is threaded in the tracking direction, and when threaded, vibration is transmitted to the main printed circuit board 11 as the transmission cable 9 is displaced. A through groove 18 is formed in the substrate 11 so as to surround the laser region 11a of the main printed circuit board to which the lead terminals 12a to 12c of the laser diode 12 are connected by soldering. And a connection region in which the connector 10 serving as a connection portion of the transmission cable 9 of the main printed circuit board 11 is separated with the through groove 18 interposed therebetween.

  Therefore, the vibration transmitted to the main printed circuit board 11 as the transmission cable 9 is displaced is divided by the through groove 18, and the influence of the vibration on the laser diode 12 is greatly reduced.

It is a perspective view which shows the assembly completion state of the optical head apparatus based on this invention. FIG. 2 is a partially developed perspective view showing a state during assembly of the optical head device shown in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Objective lens drive device 2 Objective lens 3 Optical housing 4 Lens holder 5 Support wire 6 Actuator base 7 Support plate 8a, 8b, 8c, 8d Wiring pattern 9 Transmission cable 10 Connector 11 Main printed circuit board 12 Laser diode 14 Joint part 14a Engagement Part 15 Slit (engaged part)
16a-16d Land 17a-17d of engaging part 14a Land 18 of main printed circuit board 11 Through-groove

Claims (2)

The lens holder on which the objective lens and drive coil are mounted is elastically supported by a plurality of support wires so that it can be displaced relative to the actuator base, and the drive coil mounted on the lens holder is placed in a magnetic field formed by a magnetic circuit. And an objective lens driving device for driving the objective lens by supplying a drive signal to the drive coil via a predetermined support wire, and the objective lens driving device is attached to an optical housing in which various optical elements are incorporated. An optical head device that is attached to an optical housing, and that is connected to a circuit board of a device main body on which the optical head device is mounted and a transmission cable for transmitting and receiving electrical signals; Each end of the support wire is supported and fixed by soldering to the actuator base And a support plate constituted by a printed circuit board to be defined, and a joint portion to be joined to the main printed circuit board is integrally formed on the support plate and connected to each end of the plurality of support wires. A wiring pattern is formed, and an engaging portion and an engaged portion that are engaged with each other are formed on one and the other of the main printed circuit board and the joint portion, and the engaging portion and the engaged portion Have land portions soldered to each other , and the main printed circuit board is disposed on the surface of the optical housing substantially orthogonal to the tracking direction and is positioned substantially orthogonal to the support plate, and The main printed circuit board is inserted into the notch formed in the main printed circuit board by soldering the engaging part and the engaged part, and a protruding piece of the optical housing is inserted. This is installed in the optical housing, and the main printed circuit board is connected to the lead terminal of the semiconductor laser by soldering, and is connected to a part of the main printed circuit board to which the lead terminal of the semiconductor laser is connected. An optical head device characterized in that a through groove is formed leaving a portion, and the laser region and a connection region where a connection portion of a transmission cable of the main printed circuit board is disposed are separated with the through groove interposed therebetween . The main printed circuit connecting portion of the transmission cable of the substrate is an optical head apparatus according to claim 1, characterized in that it is formed by installing a connector terminal portion of the transmission cable is inserted.

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