| 摘要 |
PURPOSE:To eliminate the connection of each coil and to ensure easy and accurate positioning of each coil, by adhering plural coils which are adhered to a flexible printed board and connected to each other via the printed board to the cylindrical circumference surface provided at the mobile part of a pickup. CONSTITUTION:For a tracking driving device, a flexible printed board 38 containing four tracking driving coils 34-37 adhered on its single side is adhered to the outer circumference of a cylindrical part 27 provided at a mobile part 8 so that each coil is set inside the outer circumfernce of the part 27. These coils 34-37 are distributed with a fixed space so that they are orthogonal to the axial core of the part 27 when they are wound round the part 27. At the same time, the normal line at the center of each coil forms 45 degrees to the lengthwise direction of a projected part 28. These coils are connected to each other by a wiring pattern 39 on the surface of the board 38 as shown in the figure. When a current is flowed to a terminal 37B from a terminal 34B, the generated magnetic fields are set opposite to each other. Then the board 38 is adhered to the part 27 so that each going path (a) turns to the inside of magnetic gaps 22 and 23 respectively. |
