Abstract: A three-phase DC motor includes a rotor having plurality of magnetic poles, and a stator. The stator has three corners. The second corner is adjacent to a first direction of the first corner. The third corner is adjacent to a second direction of the first corner. The first corner, the second corner, and the third corner extend forwards to the rotor to form a first winding slot, a second winding slot, and a third winding slot respectively. A first winding, a second winding, and a third winding respectively wind around the first winding slot, the second winding slot, and the third winding slot. The mechanical angle between the first winding slot and the second winding slot is between 75 and 85 degrees. The mechanical angle between the first winding slot and the third winding slot is also between 75 and 85 degrees.

Abstract: A voice coil motor device for positioning is disclosed. The voice coil motor device for positioning includes a fixed element, a moving element and a connector. The moving element is movably disposed on the fixed element. One end of the connector is connected with the fixed element and the other end of the connector is connected with the moving element. A piezoelectric element is disposed on the connector or deposed between the moving element and the fixed element. The piezoelectric element can be deformed with the movement of the moving element to generate a displacement signal of a moving element. The positioning of the voice coil motor can be achieved precisely basing on the judgment on the displacement signal of the moving element generated with the movement of the moving element by the piezoelectric element.

Abstract: The present invention provides a three-phase motor stator. The shape of the three-phase motor stator is defined by an optimum pole-tooth ratio for reducing the cogging torque of the motor and increasing the efficiency of the motor. The three-phase motor stator includes at least one plate board. The plate board has a circular hole. A plurality of pole-teeth protrude from the rim of the circular hole and the pole-teeth are symmetric. An opening slot is individually located between two adjacent pole-teeth. The pole-tooth ratio ? defined by the tooth angle of a single pole-tooth divided by the pole pitch of two adjacent pole-teeth is between 0.65 and 0.85.

Abstract: A method and an apparatus for estimating the position of a moving part of a linear actuator are provided. The method comprises the following steps. Move the moving part towards a target position. Receive magnetic signals generated by the magneto-resistive sensor of the linear actuator, which include a sine signal and a cosine signal. Then, generate a first square wave, a second square wave, and a regional square wave based on the sine signal and the cosine signal. Generate a saw-tooth wave based on the sine signal, the cosine signal, the second square wave, and the regional square wave. Next, calculate the number of regions which the moving part is across from the origin point based on the first square wave, the second square wave, and the regional square wave. Finally, estimate the current position of the moving part based on the saw-tooth wave and the number of regions.

Abstract: A method and an apparatus for estimating the position of a moving part of a linear actuator are provided. The method comprises the following steps. Move the moving part towards a target position. Receive magnetic signals generated by the magneto-resistive sensor of the linear actuator, which include a sine signal and a cosine signal. Then, generate a first square wave, a second square wave, and a regional square wave based on the sine signal and the cosine signal. Generate a saw-tooth wave based on the sine signal, the cosine signal, the second square wave, and the regional square wave. Next, calculate the number of regions which the moving part is across from the origin point based on the first square wave, the second square wave, and the regional square wave. Finally, estimate the current position of the moving part based on the saw-tooth wave and the number of regions.

Abstract: An optical device. At least one guide bar is connected to a base. A coil is disposed in the base. A central axis of the coil in an optical axis direction of the optical device is parallel to a central axis of the guide bar in the optical axis direction. A lens housing is slidably fitted on the guide bar. A central axis of the lens housing in the optical axis direction is parallel to that of the guide bar. The lens housing slides along the central axis of the guide bar. A magnetic member is connected to the lens housing opposite the coil, providing a first magnetic field. When the coil is energized to generate a second magnetic field, the lens housing slides on the guide bar by attraction or repulsion of the first and second magnetic fields.

Abstract: An optical device. A guide bar is connected to a base, with a first central axis in an optical axis direction of the optical device. A coil slides on the guide bar and has a second central axis in the optical axis direction and a first central elevation axis. The second central axis is perpendicular to the first central elevation axis. A fixed magnetic member is disposed in the coil and has a central magnetizing axis and a second central elevation axis. The central magnetizing axis is perpendicular to the second central elevation axis and aligned with the second central axis of the coil. The second central elevation axis is separated from the first central elevation axis. A lens housing is connected to the coil. When the coil is energized by application of a current, a magnetic force is generated, moving the coil and lens housing along the guide bar.

Abstract: An optical device. At least one guide bar is connected to a base. A coil is disposed in the base. A central axis of the coil in an optical axis direction of the optical device is parallel to a central axis of the guide bar in the optical axis direction. A lens housing slidably fits on the guide bar. A central axis of the lens housing in the optical axis direction is parallel to that of the guide bar. The lens housing slides along the central axis of the guide bar. A magnetic member is connected to the lens housing opposite the coil, providing a first magnetic field. When the coil is energized to generate a second magnetic field, the lens housing slides on the guide bar by attraction or repulsion of the first and second magnetic fields.

Abstract: A method and apparatus for making multiple layer optical discs is applied to separate the base plate from the mold plate. The apparatus includes a first adhesive ending groove, a mold plate, a sealing member and an air-blowing axle. The adhesive does not cover the area around the first and second openings and the first and second adhesive ending grooves, so an enclosed cavity is formed between the first and second openings. The air-blowing axle passes through the second opening and encloses the cavity but leaves injestion ports in the cavity so that air can be injected into the cavity for separating the base plate and the mold plate while the second recording layer and the adhesive layer adhere to the base plate.

Abstract: The invention pertains to a method for determining whether a rotor is good in magnetic induction by measuring the electromotive force (emf) of a motor. A standard stator of the motor is prepared as the standard of measurement. A set of induction coil is wound upon the standard stator so that when the rotor is combined with the standard stator and is subject to running by a driver, the induction coil can detect the back-emf signal generated by the rotor, by which the rotor quality can be determined. Since the measuring method disclosed in the invention is performed within the closed system composed of the rotor and the stator, the result is not only close to a real motor in rotation, the detection is simple and free from the problem of axis alignment. Thus, this method can increase the production efficiency of the product line.

Abstract: A film layer separation device for multilayer disks is disclosed. With the help of a stamper made of magnetic materials, the film layer separation is achieved through the attractive force imposed on the stamper by electromagnetic tearing. The device contains at least: a stamper supporter for supporting the stamper, an electromagnetic attraction device, and a base fixture. To distribute the electromagnetic force on the stamper evenly, the electromagnetic attraction device can have an array of homogeneously disposed electromagnetic iron cores and a conductive coil that can generate a magnetic force. Thus, there will be no localized stress when tearing.

Abstract: A method and apparatus for making multiple layer optical discs is applied to separate the base plate from the mold plate. The base plate is formed with a first opening, an empty zone and a data zone having a first recording layer. The apparatus includes a first adhesive ending groove, a mold plate, a sealing member and an air-blowing axle. The first adhesive-ending groove is formed on the empty zone of the base plate. The mold plate, movably pressed on the base plate, includes a main body, a second opening, a second adhesive ending groove, a second recording layer and an adhesive layer. The second opening is located on the main body at a position corresponding to the first opening of the base plate. The second adhesive-ending groove is located on the main body at a position corresponding to the first adhesive-ending groove of the base plate.

Abstract: A film layer separation device for multilayer disks is disclosed. With the help of a stamper made of magnetic materials, the film layer separation is achieved through the attractive force imposed on the stamper by electromagnetic tearing. The device contains at least: a stamper supporter for supporting the stamper, an electromagnetic attraction device, and a base fixture. To distribute the electromagnetic force on the stamper evenly, the electromagnetic attraction device can have an array of homogeneously disposed electromagnetic iron cores and a conductive coil that can generate a magnetic force. Thus, there will be no localized stress when tearing.

Abstract: The invention pertains to a method for determining whether a rotor is good in magnetic induction by measuring the electromotive force (emf) of a motor. A standard stator of the motor is prepared as the standard of measurement. A set of induction coil is wound upon the standard stator so that when the rotor is combined with the standard stator and is subject to running by a driver, the induction coil can detect the back-emf signal generated by the rotor, by which the rotor quality can be determined. Since the measuring method disclosed in the invention is performed within the closed system composed of the rotor and the stator, the result is not only close to a real motor in rotation, the detection is simple and free from the problem of axis alignment. Thus, this method can increase the production efficiency of the product line.

Abstract: The specification discloses a braking method for a single-phase motor, which is applied to a single-phase DC brushless motor driven by a three-phase motor driving IC. The invention uses a control unit to compute the rotational speed of the single-phase motor according to a rotation number signal generated by the motor rotational axis. When the rotational speed is below a threshold, the motor driving IC is controlled to stop rotating the single-phase motor. Through the single-phase motor braking method disclosed herein, the problem of unable to determine the rotational direction of a single-phase motor within a three-phase motor driving IC existing in the prior art can be solved by merely modifying the program in the control unit without adding system elements.

Abstract: The present invention is a starting method for brushless DC motor and a device for the same, especially adapted to provide the starting method for a single-phase DC brushless motor in an open circuit and the device for the same. According to the art as disclosed in the present invention, there are two successive steps in starting a motor. An oscillator signal is transmitted to the driver at first, which causes the motor to oscillate in both clockwise and counter-clockwise direction. An operating signal is then sent to cause the motor to rotate normally in one direction once the motor is out of the dead initiating position. By that the rotor can be triggered out of the dead initiating position when the motor is going to start and the motor can be smoothly operated under the low cogging torque.