Abstract: A brake device arranged between a drive shaft and a driven shaft arranged coaxially with the drive shaft is disclosed. The brake device includes a first rotor, a second rotor, an engagement member, a braking mechanism, and a cam mechanism. The braking mechanism includes a movable friction member rotatable integrally with the second rotor, a fixed friction portion, and an urging member that urges the movable friction member toward the fixed friction portion. When rotational force is provided from the drive shaft to the first rotor, the cam mechanism permits transmission of rotation of the drive shaft to the driven shaft. When the rotational force is provided from the driven shaft to the second rotor, the cam mechanism restricts rotation of the driven shaft. The cam mechanism is provided independently from the engagement member.

Abstract: Sounds in different frequency range are generated from the rear, top and/or front face of the musical tone apparatus, sounds are generated and spread in all directions around the musical tone apparatus, and the tones sound very realistically acoustic. Vibration of the sound board does not resonate, tones generated from the sound board are not changed unintentionally, and tones of real acoustic musical instruments are realized. Vibration from the sound board is not directly transferred to the whole musical tone apparatus, by means of not allowing the sound board to touch the body of the musical tone apparatus and of pressing and fixing the soundboard to the attachment component with the thickness of the attachment component compressed.

Abstract: A commutator having a plurality of segments, a short-circuit member assembly, a holding portion, and a plurality of spacing members is disclosed. The short-circuit member assembly includes a plurality of short-circuit pieces. Each short-circuit piece has an outer terminal, an inner terminal arranged radially inward from the outer terminal and circumferentially offset from the outer terminal at a predetermined offset angle, and a connecting portion connecting the inner terminal to the outer terminal. The holding portion covers the segments and at least a portion of the short-circuit member assembly to hold the segments and the short-circuit member assembly. The spacing members each have an insulated support portion and a plurality of insulated spacing projections formed integrally with the support portion. Each support portion extends in a radial direction of the short-circuit member assembly.

Abstract: A brake device arranged between a drive shaft and a driven shaft arranged coaxially with the drive shaft is disclosed. The brake device includes a first rotor, a second rotor, an engagement member, a braking mechanism, and a cam mechanism. The braking mechanism includes a movable friction member rotatable integrally with the second rotor, a fixed friction portion, and an urging member that urges the movable friction member toward the fixed friction portion. When rotational force is provided from the drive shaft to the first rotor, the cam mechanism permits transmission of rotation of the drive shaft to the driven shaft. When the rotational force is provided from the driven shaft to the second rotor, the cam mechanism restricts rotation of the driven shaft. The cam mechanism is provided independently from the engagement member.

Abstract: A commutator having a plurality of segments, a short-circuit member assembly, a holding portion, and a plurality of spacing members is disclosed. The short-circuit member assembly includes a plurality of short-circuit pieces. Each short-circuit piece has an outer terminal, an inner terminal arranged radially inward from the outer terminal and circumferentially offset from the outer terminal at a predetermined offset angle, and a connecting portion connecting the inner terminal to the outer terminal. The holding portion covers the segments and at least a portion of the short-circuit member assembly to hold the segments and the short-circuit member assembly. The spacing members each have an insulated support portion and a plurality of insulated spacing projections formed integrally with the support portion. Each support portion extends in a radial direction of the short-circuit member assembly.

Abstract: Sounds in different frequency range are generated from the rear, top and/or front face of the musical tone apparatus, sounds are generated and spread in all directions around the musical tone apparatus, and the tones sound very realistically acoustic. Vibration of the sound board does not resonate, tones generated from the sound board are not changed unintentionally, and tones of real acoustic musical instruments are realized. Vibration from the sound board is not directly transferred to the whole musical tone apparatus, by means of not allowing the sound board to touch the body of the musical tone apparatus and of pressing and fixing the soundboard to the attachment component with the thickness of the attachment component compressed.

Abstract: A brush holder is installed to a motor main body and has a connector arrangement, which is directly connectable with an external connector to receive electric power. The brush holder holds a plurality of power supply brushes. A control circuit member is installed in a gear housing through an installation opening of the gear housing. The control circuit member controls rotation of the motor main body and is electrically connected to the connector arrangement and the power supply brushes.

Abstract: A brush holder is installed to a motor main body and has a connector arrangement, which is directly connectable with an external connector to receive electric power. The brush holder holds a plurality of power supply brushes. A control circuit member is installed in a gear housing through an installation opening of the gear housing. The control circuit member controls rotation of the motor main body and is electrically connected to the connector arrangement and the power supply brushes.

Abstract: A brush holder is installed to a motor main body and has a connector arrangement, which is directly connectable with an external connector to receive electric power. The brush holder holds a plurality of power supply brushes. A control circuit member is installed in a gear housing through an installation opening of the gear housing. The control circuit member controls rotation of the motor main body and is electrically connected to the connector arrangement and the power supply brushes.

Abstract: A brush holder is installed to a motor main body and has a connector arrangement, which is directly connectable with an external connector to receive electric power. The brush holder holds a plurality of power supply brushes. A control circuit member is installed in a gear housing through an installation opening of the gear housing. The control circuit member controls rotation of the motor main body and is electrically connected to the connector arrangement and the power supply brushes.

Abstract: An acoustic control system for an electronic musical instrument, which can obtain optimal acoustic characteristics irrespective of whether or not a low range speaker is attached to a body thereof. A piano body has high range and mid range speakers. A low range speaker is removable from the body. A stand-excluding switch designates a first speaker-use mode for using the high range and mid range speakers alone, and a stand-including switch designates a both speaker-use mode for using both the high range and mid range speakers and the low range speaker. A ROM stores stand-excluding and stand-including factors for setting acoustic characteristics in the two modes, respectively. A CPU reads one of the factors, which corresponds to the mode designated by the stand-excluding or stand-including switch. A tone generator circuit generates a musical tone signal to be reproduced in one of the modes, based on the read factor.

Abstract: A driving apparatus is disclosed for driving a driven device such as a lifting mechanism (8) for moving up and down a windowpane (9). The driving apparatus comprises a motor (5) including a rotating shaft (13), and an output unit (6; 80) coupled to the motor. The output unit comprises a decelerating mechanism (42, 43, 56; 56, 92) for decelerating the rotation of the rotating shaft. A clutch (21; 71; 81; 200; 300) is located between the rotating shaft and the decelerating mechanism. The clutch allows transmission of rotation from the rotating shaft to the decelerating mechanism, and blocks transmission of rotation from the decelerating mechanism to the rotating shaft. The clutch located between the rotating shaft and the decelerating mechanism is not applied with a large load. For this reason, the strength required for the clutch can be reduced to provide the clutch in a smaller size.

Abstract: A motor main body includes a brush holder, which supports a plurality of power supply brushes and includes a motor-side connector to be connected with an external connector. A circuit board is installed to the brush holder in a direction perpendicular to an axial direction of a rotatable shaft to electrically connect between the motor-side connector and the power supply brushes. The circuit board is received in the circuit board receiving portion when the motor main body and a speed reducing unit are assembled together to form an electric motor.

Abstract: A motor main body includes a brush holder, which supports a plurality of power supply brushes and includes a motor-side connector to be connected with an external connector. A circuit board is installed to the brush holder in a direction perpendicular to an axial direction of a rotatable shaft to electrically connect between the motor-side connector and the power supply brushes. The circuit board is received in the circuit board receiving portion when the motor main body and a speed reducing unit are assembled together to form an electric motor.

Abstract: A rotational sensor of a motor includes a sensor magnet and a sensing element. The sensor magnet is secured to a driving-side rotator of a clutch, which is connected to a rotatable shaft of the motor, to rotate integrally therewith. The sensing element measures a rotational speed of the sensor magnet. Furthermore, the sensing element is secured to a motor case in such a manner that the sensing element opposes the sensor magnet.

Abstract: A yoke housing that receives an armature has a plurality of permanent magnets (primary magnetic poles) secured to an inner peripheral surface of the yoke housing. Furthermore, the yoke housing includes a plurality of groove-like reduced thickness portions for increasing a magnetic resistance. Each reduced thickness portion extends along a center line of a corresponding one of the permanent magnets.

Abstract: An acoustic control system for an electronic musical instrument, which can obtain optimal acoustic characteristics irrespective of whether or not a low range speaker is attached to a body thereof. A piano body has high range and mid range speakers. A low range speaker is removable from the body. A stand-excluding switch designates a first speaker-use mode for using the high range and mid range speakers alone, and a stand-including switch designates a both speaker-use mode for using both the high range and mid range speakers and the low range speaker. A ROM stores stand-excluding and stand-including factors for setting acoustic characteristics in the two modes, respectively. A CPU reads one of the factors, which corresponds to the mode designated by the stand-excluding or stand-including switch. A tone generator circuit generates a musical tone signal to be reproduced in one of the modes, based on the read factor.

Abstract: A geared motor includes a yoke and a gear housing. The gear housing includes a worm housing segment and a wheel housing segment. A shaft supporting portion is formed for supporting an output shaft at a center of a base wall of the wheel housing segment. Ribs extend radially outwardly from the shaft supporting portion along an outer surface of the base wall of the wheel housing segment. A lateral thickness of each rib is equal to or smaller than an axial thickness of the base wall of the wheel housing segment.

Abstract: In a geared motor, a cover plate is fitted to an opening of a housing of a geared motor. The cover plate includes an output shaft hole, a rib and a short cylindrical portion. The output shaft hole penetrates through a center of the cover plate and rotatably receives an output shaft therethrough. The rib is formed along an outer peripheral edge of the cover plate and is radially supported by the housing. The short cylindrical portion is slidably engageable with an outer peripheral surface of the output shaft for radially supporting the output shaft. An inner peripheral surface of a worm wheel is slidably engageable in line contact with a sliding ridge of a disk plate of the output shaft.

Abstract: A clutch comprises a driving rotor (11; 52; 83; 202; 302) coupled to a driving source (2) such as a motor, and a driven rotor (12; 53; 85; 204; 303) directly engaged with the driving rotor. Both rotors are accommodated in a housing (13; 51; 82; 201; 301). A lock member (14; 54; 86; 119; 205; 304) comprised of rollers or balls is located between the driven rotor and the housing. When the driven rotor itself is rotated, the lock member is held between the driven rotor and the housing to block the rotation of the driven rotor relative to the housing. When the driving source rotates the driving rotor, the lock member is released from the held state to allow the driving rotor to rotate the driven rotor relative to the housing. Such a clutch can block the transmission of the rotation from the driven rotor to the driving rotor without fail, and can reduce the strength required to both rotors.