JP5373716B2 - Optical pickup - Google Patents

Description

  The present invention relates to an optical pickup capable of reproducing and recording a signal on a disk such as a CD or a DVD, and more particularly, an electrical and mechanical connection with a circuit board of a set device derived from a main body of the optical pickup. It is related with the flexible printed circuit board connected to.

  An optical pickup is mainly composed of a main body portion in which a light emitting / receiving unit and an objective lens are mounted on a chassis, and a flexible printed circuit board (hereinafter abbreviated as “FPC”) derived from the main body portion for signal transmission. Has been. The light receiving / emitting unit is integrally provided with a semiconductor laser as a light source and a light receiving element such as a photodetector. An FPC for signal transmission is a belt-like body in which a large number of conductor patterns are arranged on one side of a flexible base film, and each conductor pattern is almost insulated except for both ends. . One end of the FPC is connected to the main body, and the other end of the FPC is connected to a circuit board of a set device such as an optical disc player as an external connection end. This circuit board is provided with a drive control circuit for controlling a semiconductor laser and the like, and a signal processing circuit for processing an output signal of the light receiving element, and is usually a conductor pattern disposed at an external connection end of the FPC. The front end portion (connection terminal) of the circuit board is connected to a corresponding connection land of the circuit board using a connector.

  The basic operation of the optical pickup incorporated in the set device will be described. This optical pickup is a light beam emitted from the semiconductor laser while moving the main body in the radial direction of the disk loaded in the set device. Is focused on the recording surface of the disc by the objective lens, and the return light beam from the disc is received by the light receiving element via the objective lens. Since the main body is electrically connected to the drive control circuit and signal processing circuit on the set device side via the FPC, the operation of the optical pickup causes the signal recorded on the disk to be reproduced or erased or to the disk. Signal recording or the like becomes possible.

  In general, in the manufacturing process of this type of optical pickup, the optical pickup is actually operated by pressing the contact pins of the inspection device against the conductor pattern of the FPC before being incorporated in the set equipment, While performing the adjustment work, an inspection is performed to confirm that the pickup is a non-defective product that does not cause poor conduction or malfunction. For this reason, the external connection end portion of the FPC of the optical pickup is provided with a window portion in which the conductor pattern is exposed for inspection (see, for example, Patent Document 1). Further, as described above, since the end portion for external connection of the FPC is connected to the circuit board of the set device via the connector, a supplementary material for reinforcing the base film from the back side is provided on the end portion for external connection of the FPC. The mechanical strength of the FPC that is necessary when the external connection end is inserted into the connector is secured by this auxiliary material. This auxiliary material also plays a role of preventing undesired deformation of the FPC, which is a concern during inspection in which the contact pins of the inspection apparatus are pressed against the conductor pattern.

JP 2010-108543 A

  Incidentally, the structure in which the FPC of the optical pickup and the circuit board of the set device are connected via a connector has an advantage that the FPC can be easily attached to and detached from the circuit board, but is expensive in terms of cost. Therefore, it was not preferable from the viewpoint of promoting cost reduction of the set equipment. In other words, FPC connectors are relatively expensive and are likely to increase the cost of components, and it is necessary to perform gold plating on the connection portion between the FPC and the connector to ensure the reliability of conduction. The required processing cost is likely to increase.

  The present invention has been made in view of the actual situation of the prior art, and an object of the present invention is to provide an optical pickup capable of connecting an FPC to a circuit board of a set device at a low cost and easily ensuring reliability of conduction. There is.

  In order to achieve the above object, the present invention comprises at least a main body portion on which a light emitting / receiving unit and an objective lens are mounted, and a flexible printed circuit board for signal transmission derived from the main body section, and the flexible printed circuit board. In the optical pickup in which the external connection end portion of the flexible printed circuit board is electrically and mechanically connected to the circuit board of the set device. A part of each conductor pattern provided at the end for external connection is exposed for inspection, and the tip of each conductor pattern is not a connection terminal soldered to a connection land provided on the circuit board. In addition, the base frame is formed in a region where the tip region where the connection terminal exists is removed from the external connection end. And the configuration of fixing a stiffener for reinforcing the Lum from the back side.

  In the optical pickup configured in this way, each end portion of the conductor pattern group existing at the external connection end portion of the FPC is formed as a connection terminal that is directly soldered to the circuit board of the set device. An expensive FPC connector can be omitted, and it becomes easy to ensure the reliability of conduction without expensive plating. In addition, since the conductor pattern group exposed for inspection at the external connection end of the FPC is reinforced by the auxiliary material from the back side, the external connection end is not present during the inspection in which the contact pin of the inspection apparatus is pressed. There is no risk of deformation and damage as desired. In addition, since this auxiliary material is not provided in the tip region of the external connection end portion where the connection terminal group exists, there is a large step caused by the auxiliary material between each connection terminal and the corresponding connection land of the circuit board. There is no possibility of occurrence, and soldering between the connection terminal and the connection land can be easily and reliably performed.

  In the above configuration, when the length of the auxiliary material along the arrangement direction of the connection terminal group is set larger than the tip region of the FPC external connection end, the external connection end is used as an inspection device. At the time of mounting, easy and accurate positioning can be performed by bringing the corner portion on the distal end side of the auxiliary material rich in mechanical strength into contact with the stopper portion of the inspection apparatus.

  In the above configuration, a plurality of reference holes are provided in the circuit board, and a plurality of positioning holes are provided in a region where the auxiliary material is present in the external connection end portion of the FPC. When the external connection ends are arranged on the circuit board in a state where they are matched, the external connection ends are connected to the circuit board when each connection terminal is arranged on the corresponding connection land. In this case, easy and accurate positioning can be performed by using an auxiliary material having a high mechanical strength. In this case, a reinforcing land having a through hole is provided in a region on the base side of the FPC external connection end, and the dummy land is disposed in a state where the through hole is disposed on the dummy land provided on the circuit board. When the lands and the reinforcing lands are soldered, the mounting strength of the FPC (external connection end) to the circuit board can be significantly increased.

  According to the optical pickup of the present invention, each end portion of the conductor pattern group existing on the external connection end portion of the FPC is formed as a connection terminal that is directly soldered to the circuit board of the set device. The connector is not necessary, and the external connection end can be connected to the circuit board at a low cost, and the reliability of conduction can be improved without performing an expensive plating process. In addition, since the conductor pattern group exposed for inspection at the external connection end of the FPC is reinforced by the auxiliary material from the back side, the external connection end is not present during the inspection in which the contact pin of the inspection apparatus is pressed. It can be prevented from being deformed and damaged as desired. In addition, since this auxiliary material is not provided in the tip region of the external connection end where the connection terminal group exists, there is a large step caused by the auxiliary material between each connection terminal and the corresponding connection land of the circuit board. There is no risk of this occurring, and therefore, the soldering between the connection terminal and the connection land can be performed easily and reliably.

1 is a top view of an optical pickup according to an embodiment of the present invention. It is a principal part enlarged view of FIG. It is a bottom view of the optical pickup shown in FIG. It is a principal part enlarged view of FIG. It is a perspective view which shows the state which mounted | wore the test | inspection apparatus with FPC of this optical pick-up. FIG. 6 is a top view corresponding to FIG. 5. FIG. 6 is a side view corresponding to FIG. 5. It is a principal part perspective view of the circuit board of the set apparatus in which this optical pick-up is integrated. It is a principal part top view corresponding to FIG. It is a principal part perspective view which shows the state which soldered FPC of this optical pick-up to the circuit board of a set apparatus. It is a principal part top view corresponding to FIG.

  Embodiments of the present invention will be described below with reference to FIGS. The optical pickup 1 shown in FIGS. 1 to 4 includes a main body portion 2 in which a light emitting / receiving unit 4 and an objective lens 5 are mounted on a chassis 6, and an FPC for signal transmission derived from the main body portion 2 in a band shape ( Flexible printed circuit board) 3. This optical pickup 1 is used by being incorporated in an optical disc player (such as a CD player or a DVD player) that is a set device. As shown in FIGS. 10 and 11, an external connection end at the tip of the FPC 3 is used. The unit 9 is connected to the circuit board 20 of the set device. The circuit board 20 is provided with a drive control circuit and a signal processing circuit for the optical pickup 1.

  The chassis 6 that forms the outer shell of the main body 2 is incorporated in a set device so as to reciprocate along the radial direction of the disk. The light receiving / emitting unit 4 is integrally provided with a semiconductor laser serving as a light source and a light receiving element such as a photodetector. The position of the objective lens 5 is controlled in the focus direction and the tracking direction by electromagnetic driving means including a magnetic circuit and a coil. Then, by incorporating the optical pickup 1 into the set device, these electromagnetic drive means and semiconductor laser are controlled by the drive control circuit via the FPC 3, and the output signal of the light receiving element is processed by the signal processing circuit. Will be.

  The FPC 3 for signal transmission is a belt-like body in which a large number of conductor patterns 7 are arranged on one side of a flexible base film 8, and each conductor pattern 7 is substantially insulatively coated except for both ends. Has been. One end side of the FPC 3 is connected to the main body 2, and the other end side of the FPC 3 is an external connection end portion 9 connected to the circuit board 20 of the set device. As shown in FIG. 2, connection terminals 7 a corresponding to the respective tip portions of the conductor pattern 7 group are arranged in the tip region 9 a of the external connection end portion 9. Since the connection land 21 (see FIG. 8) provided on the substrate 20 is directly soldered, a connector is not necessary for connection between the FPC 3 and the circuit substrate 20. Further, a rectangular window portion 9d extending substantially parallel to the connection terminal 7a group is provided at a position slightly away from the tip region 9a of the external connection end portion 9, and the conductor pattern 7 group is exposed from the window portion 9d. It is. This window portion 9d is formed as a place where an insulating layer covering the conductor pattern 7 group does not exist. As shown in FIGS. 5 to 7, the inspection clip 30 is formed on the conductor pattern 7 group exposed in the window portion 9d. The contact pin 31 group can be pressed.

  As shown in FIG. 2, positioning holes 9 b and 9 c are formed in a region where the conductor pattern 7 does not exist in the external connection end 9 of the FPC 3. These positioning holes 9b and 9c are formed in the same positional relationship as a pair of reference holes 23 and 24 (see FIG. 8) provided in the circuit board 20, and the positioning holes 9b and 9c are inserted into the reference holes 23 and 9c. By arranging the external connection end portion 9 on the circuit board 20 in a state of being matched with 24, each connection terminal 7a is arranged on the corresponding connection land 21. In order to absorb a dimensional error within a tolerance range, one positioning hole 9b is a round hole, whereas the other positioning hole 9c is formed as a long hole. Further, in a region on the base side of the external connection end portion 9, there are a through hole 9e disposed on the dummy land 22 (see FIG. 8) of the circuit board 20, and a reinforcing land 9f surrounding the through hole 9e. Is provided. When connecting the external connection end 9 to the circuit board 20, the reinforcing land 9 f is soldered to the dummy land 22 in order to increase the attachment strength.

  Further, a reinforcing auxiliary material 10 is fixed (adhered) to the external connection end 9 of the FPC 3 on the back side of the base film 8 except for the front end region 9a. The auxiliary material 10 is set to have a slightly larger length dimension along the arrangement direction of the connection terminals 7a than the distal end region 9a. The pair of corners 10a on the distal end side of the auxiliary material 10 has both ends of the distal end region 9a. A notch-shaped step is formed on the side. Both corners 10 a function as positioning portions during inspection when the external connection end 9 is attached to the inspection clip 30. The positioning holes 9 b and 9 c and the through hole 9 e of the external connection end 9 are formed through the auxiliary material 10 and the base film 8.

  The optical pickup 1 configured as described above is a non-defective product that performs a light beam adjustment operation in an energized state before being incorporated into a set device and that the optical pickup 1 does not cause poor conduction or malfunction. An inspection is performed to confirm whether or not. At the time of such inspection, a conductor pattern that exposes the contact pin 31 group of the inspection clip 30 in the window portion 9d after the external connection end 9 of the FPC 3 is correctly attached to the inspection clip 30 shown in FIGS. The required continuity test is performed by contacting the 7 groups. The inspection clip 30 has a structure in which a movable portion 30a provided with a group of contact pins 31 and a placement portion 30b provided with a pair of clamp switches 32 are hinge-coupled. And are electrically connected. Then, at the time of inspection, the movable portion 30a is opened and the external connection end portion 9 of the FPC 3 is arranged at a predetermined position on the placement portion 30b. Since it can position in the left-right direction, if a pair of corner part 10a of the auxiliary material 10 is pressed on the wall surface of a pair of clamp switch 32, this wall surface becomes a stopper part and can also position the auxiliary material 10 also in the front-back direction. . Therefore, the external connection end portion 9 can be easily and accurately arranged at a predetermined position on the mounting portion 30b. If the movable portion 30a is closed in this state, each conductor pattern 7 exposed in the window portion 9d is exposed. The corresponding contact pin 31 can be reliably pressed.

  Since the conductor pattern 7 group exposed in the window portion 9d of the external connection end portion 9 is carried on the base film 8 reinforced by the auxiliary material 10, contact pins are connected to these conductor patterns 7. There is no possibility that the external connection end portion 9 is undesirably deformed and damaged during the above-described inspection in which the pressure contact 31 is pressed.

  The optical pickup 1 that is confirmed to be a non-defective product by the above-described inspection is incorporated into a set device, and the external connection end 9 of the FPC 3 is connected to the circuit board 20. As described above, the connection terminal 7a of the external connection end 9 is directly soldered to the corresponding connection land 21 of the circuit board 20, so that the FPC 3 and the circuit board 20 are connected as shown in FIGS. No connector is required. Further, since the auxiliary material 10 attached to the external connection end portion 9 is not provided in the distal end region 9a where the connection terminal 7a group exists, the auxiliary material 10 is provided between the connection terminal 7a and the connection land 21. The resulting large step does not occur.

  The optical pickup 1 incorporated in the set device uses the objective lens 5 to transmit the light beam emitted from the semiconductor laser of the light emitting / receiving unit 4 while moving the main body 2 in the radial direction of the disk loaded in the set device. The light is condensed on the recording surface of the disk, and the return light beam from the disk is received by the light receiving element of the light receiving and emitting unit 4 via the objective lens 5. Since the main body 2 is electrically connected to the drive control circuit and signal processing circuit of the circuit board 20 via the FPC 3, the operation of the optical pickup 1 can reproduce or erase the signal recorded on the disc. It is possible to record signals on the disc.

  As described above, in the optical pickup 1 according to the present embodiment example, the connection in which each tip portion of the conductor pattern 7 group existing on the external connection end portion 9 of the FPC 3 is directly soldered to the circuit board 20 of the set device. Since it is formed as the terminal 7a, a relatively expensive FPC connector can be omitted, and the reliability of conduction can be ensured without performing a special plating process. Further, since the conductor pattern 7 group exposed for inspection in the window portion 9d of the external connection end portion 9 is reinforced by the auxiliary material 10 from the back side, the contact pin 31 of the inspection clip 30 (inspection apparatus). There is no possibility that the external connection end portion 9 is undesirably deformed and damaged at the time of inspection for press-contacting. Further, since the auxiliary material 10 is not provided in the tip region 9a of the external connection end portion 9 where the group of connection terminals 7a exists, the auxiliary material 10 is provided between each connection terminal 7a and the corresponding connection land 21 of the circuit board 20. A large step due to the material 10 does not occur, and therefore, the soldering between the connection terminal 7a and the connection land 21 can be performed easily and reliably.

  Further, in the optical pickup 1 according to this embodiment, the length of the auxiliary material 10 along the arrangement direction of the group of connection terminals 7a is larger than that of the distal end region 9a of the external connection end 9 of the FPC 3. A pair of corners 10a on the distal end side of the auxiliary material 10 is formed with notched step portions on both sides of the distal end region 9a. Then, at the time of inspection for confirming that the manufactured optical pickup 1 is a non-defective product, the external connection end portion 9 can be disposed at a predetermined position of the inspection clip 30 with the both corner portions 10a serving as positioning portions. Therefore, it is possible to easily and accurately position the external connection end 9 with respect to the inspection clip 30 by using the auxiliary material 10 having a high mechanical strength.

  In the optical pickup 1 according to this embodiment, the same positional relationship as the reference holes 23 and 24 provided in the circuit board 20 of the set device in the region where the auxiliary material 10 exists in the external connection end 9 of the FPC 3. Positioning holes 9b and 9c are provided, and the external connection end 9 is arranged on the circuit board 20 in a state in which the reference holes 23 and 24 and the positioning holes 9b and 9c are aligned with each other. The terminals 7a are arranged on the corresponding connection lands 21. Therefore, when connecting the external connection end 9 of the FPC 3 to the circuit board 20, it is easy to position the external connection end 9 with respect to the circuit board 20 by using the auxiliary material 10 having high mechanical strength. Can be done accurately.

  Further, in the optical pickup 1 according to the present embodiment, a through hole 9e and a reinforcing land 9f that are disposed on the dummy land 22 of the circuit board 20 are provided in a region on the base side of the external connection end 9 of the FPC 3. Since the reinforcing land 9f is soldered to the dummy land 22, the attachment strength of the FPC 3 (external connection end 9) to the circuit board 20 can be greatly increased. If the soldering of the reinforcing lands 9f and the dummy lands 22 and the soldering of the connecting terminals 7a and the connecting lands 21 are collectively performed by a reflow process or the like, an increase in the soldering process is avoided. it can.

1 Optical Pickup 2 Body 3 FPC (Flexible Printed Circuit Board)
DESCRIPTION OF SYMBOLS 4 Light emitting / receiving unit 5 Objective lens 7 Conductor pattern 7a Connection terminal 8 Base film 9 External connection end part 9a Tip area 9b, 9c Positioning hole 9d Window part 9e Through hole 9f Reinforcement land 10 Supplementary material 10a Corner part 20 Circuit board 21 Connection Land 22 Dummy land 23, 24 Reference hole 30 Inspection clip (Inspection device)
31 Contact pin 32 Clamp switch (stopper)

Claims (4)

At least a main body portion on which a light emitting / receiving unit and an objective lens are mounted, and a flexible printed circuit board for signal transmission derived from the main body section, the flexible printed circuit board has a base film that carries a conductor pattern group, In the optical pickup in which the external connection end of the flexible printed circuit board is electrically and mechanically connected to the circuit board of the set device.
A portion of each conductor pattern disposed on the external connection end of the flexible printed circuit board is exposed for inspection, and the tip of each conductor pattern is soldered to a connection land provided on the circuit board. And an auxiliary material that reinforces the base film from the back side is fixed to a region of the external connection end portion from which the tip region where the connection terminal exists is removed. Expression pickup.   2. The optical pickup according to claim 1, wherein the length of the auxiliary material along the arrangement direction of the connection terminal group is set larger than that of the distal end region of the external connection end portion. .   3. The circuit board according to claim 1, wherein a plurality of reference holes are provided in the circuit board, and a plurality of positioning holes are provided in a region where the auxiliary material is present at the end portion for external connection. The optical pickup is characterized in that the connection terminals are arranged on the corresponding connection lands by arranging the end portions for external connection on the circuit board in a state where they are matched.   4. The dummy land according to claim 3, wherein a reinforcing land having a through hole is provided in a region on a base side of the end portion for external connection, and the through hole is disposed on a dummy land provided on the circuit board. An optical pickup characterized in that a land and the reinforcing land are soldered.

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