Abstract: A speaker may include a center pole and a voice coil bobbin having a bobbin that may include nonmagnetic and electric conductor layers and insulator layers disposed between the electric conductor layers. An electrostatic capacity, which is formed between the center pole and the voice coil bobbin, is detected and outputted as an electrical signal.

Abstract: A speaker may include a voice coil bobbin and a center pole. The voice coil bobbin may include a nonmetallic pipe body as a base of the voice coil bobbin, a first nonmagnetic and electric conductor film which is formed on an inner peripheral face of the pipe body, and a second electric conductor film which is formed on an outer peripheral face of the pipe body such that the first electric conductor film is covered by the second electric conductor film through the pipe body. An electrostatic capacity that is formed between the voice coil bobbin and the center pole is detected and outputted as an electric signal.

Abstract: A speaker may include a center pole, a voice coil bobbin having a nonmetallic pipe body, and a first and a second electrodes which are provided on an inner peripheral face of the pipe body for detecting an electrostatic capacity. The first and the second electrodes are disposed so as to be separated from each other with a predetermined space along an axial direction of the center pole. Further, a stepped portion may be formed in the side circumferential face of the center pole such that, when the voice coil bobbin is operated, a first facing area of the first electrode to the side circumferential face defined by the stepped portion of the center pole increases while a second facing area of the second electrode to the side circumferential face defined by the stepped portion of the center pole decreases by a same amount as an increased amount of the first facing area.

Abstract: A speaker may include a center pole, a voice coil bobbin having a nonmetallic pipe body, and a first and a second electrodes which are provided on an inner peripheral face of the pipe body for detecting an electrostatic capacity. The first and the second electrodes are disposed so as to be separated from each other with a predetermined space along an axial direction of the center pole. Further, a stepped portion may be formed in the side circumferential face of the center pole such that, when the voice coil bobbin is operated, a first facing area of the first electrode to the side circumferential face defined by the stepped portion of the center pole increases while a second facing area of the second electrode to the side circumferential face defined by the stepped portion of the center pole decreases by a same amount as an increased amount of the first facing area.

Abstract: A speaker may include a center pole, a voice coil bobbin having a pipe body, and at least one or more electrodes which are disposed on the pipe body to detect an electrostatic capacity formed between the electrode and a side circumferential face of the center pole. The pipe body is comprised of a flexible board on which the electrode is formed. The flexible board may include a strip-shaped electric line drawing-out part which is formed with a film being extended from an edge portion of the pipe body, and the electric line drawing-out part is structured of the film on which an output line connected to a movable electrode and a grounded line connected to another electrode are printed.

Abstract: A speaker may include a center pole, a voice coil bobbin, a support member that supports at least one of the center pole and the voice coil bobbin, and a converter circuit for converting an electrostatic capacity which is formed between the center pole and the voice coil bobbin into an electric signal to be outputted. The converter circuit is provided on either of the support member and the center pole and may be disposed at the tip end of the center pole.

Abstract: A speaker may include a voice coil bobbin and a center pole. The voice coil bobbin may include a nonmetallic pipe body as a base of the voice coil bobbin, a first nonmagnetic and electric conductor film which is formed on an inner peripheral face of the pipe body, and a second electric conductor film which is formed on an outer peripheral face of the pipe body such that the first electric conductor film is covered by the second electric conductor film through the pipe body. An electrostatic capacity that is formed between the voice coil bobbin and the center pole is detected and outputted as an electric signal.

Abstract: A speaker may include a center pole and a voice coil bobbin having a bobbin that may include nonmagnetic and electric conductor layers and insulator layers disposed between the electric conductor layers. An electrostatic capacity, which is formed between the center pole and the voice coil bobbin, is detected and outputted as an electrical signal.

Abstract: Odd- and even-numbered conductors of recording electrodes, for example, first or second recording electrodes, are divided in the direction in which the conductor at the time of winding are stacked up to form different layers so as to increase the distance between the conductors of the adjoining recording electrodes and reduce the floating electrostatic capacitance.