31
Michael I Kellogg, M Robert Mock: Brushless DC motors with remote Hall sensing and methods of making the same. HR Textron, BainwoodHuang, August 22, 2006: US07095193 (14 worldwide citation)

A brushless DC motor apparatus includes a housing and a stator assembly coupled to the housing. The apparatus further includes a magnetic rotor assembly rotatably coupled to the housing. The magnetic rotor assembly is configured to rotate within the housing in response to electric currents through w ...


32
Robert G Brown: Extrapolation of back EMF signals in brushless DC motors. The Bergquist Torrington Company, Haugen Law Firm PLLP, Frederick W Niebuhr, April 6, 2010: US07692395 (14 worldwide citation)

A controller is provided for operating a DC motor through a commutation circuit and for synchronizing the commutation circuit to motor position and speed by measuring back EMF voltages along commutation cycle steps during which the measured phase is not being driven. In connection with each such ste ...


33
Yasuhiro Okada: Load and supply voltage sensitive speed control system for DC brushless fan motors. Matsushita Electric Industrial, Amster Rothstein & Ebenstein, October 8, 1996: US05563480 (14 worldwide citation)

A speed control system for brushless DC motors which maintains the rotational speed of the motor substantially constant even when the motor load and/or supply voltage fluctuates. Furthermore, by including a negative-resistance temperature coefficient thermistor in the speed control system, the rotat ...


34
Byung H Min, Seung K Park: Driving methods and driving circuits for brushless DC motors without rotor position sensors. Goldstar, Goldstar Electron, Rosen Dainow & Jacobs, November 24, 1992: US05166583 (14 worldwide citation)

A sensorless and brushless DC motor in which phase-corresponding coils are turned on at an electric angle of 180.degree..


35
Kenkichi Tarumi, Junichi Kanamori: Brushless DC motors. Sansui Electric, Harris Kern Wallen & Tinsley, June 19, 1979: US04158795 (14 worldwide citation)

A brushless DC motor capable of change of rotational direction is disclosed. The feed of a high-frequency voltage signal to switching elements is sequentially changed to orderly excite stator windings by the outputs from rotor angular position detectors so that the rotor is rotated in a desired dire ...


36
John J Maney: Digital pulse width modulation control of brushless DC motors. Harris Corporation, Antonelli Terry & Wands, December 26, 1989: US04890047 (13 worldwide citation)

An improved torque control for a brushless DC motor is disclosed. A torque command A of a time varying nature is applied to an excitation winding which is magnetically coupled through a resolver to produce output signals respectively on sensing windings of Acosine .theta. and of Asine .theta. wherei ...


37
Hao Huang: Virtual hall-effect signal generating for a brushless sensorless electrical rotary machine. SL Montevideo Technology, Nixon & Vanderhye, November 21, 1995: US05469033 (12 worldwide citation)

Electronic solid state circuitry is provided which takes the place of Hall-effect sensors in brushless DC motors, providing output signals substantially the same as those of Hall-effect sensors. The Hall-effect sensors in existing motors may be deactivated or removed and functionally replaced by the ...


38
Masaya Okita, Masahiro Sawada, Tadashi Ota: Drive circuit for brushless DC motors. Nippon Kogaku, Michael N Meller, December 1, 1987: US04710684 (12 worldwide citation)

A drive circuit for a brushless DC motor capable of generating a torque in the acceleration and deceleration directions, respectively, and effective when used in a portable device such as an electronic still picture camera. In the drive circuit, a power amplifier having an output stage composed of a ...


39
Karl M Schlager, Francesco Carobolante, Solomon K Ng: Circuitry for switching the body nodes of driver transistors in drive circuitry for brushless DC motors. SGS Thomson Microelectronics, Rodney M Anderson, Lisa K Jorgenson, Richard K Robinson, May 7, 1996: US05514939 (12 worldwide citation)

Circuitry for selectably connecting the body node of drive transistors of a motor control circuit. In particular, those transistors that are turned off when operating the motor in a unipolar mode have their body nodes switched so as to be connected to a reference voltage, such as ground, during unip ...


40
Michael John Werson: Brushless DC motors. Automotive Motion Technology, Renner Otto Boisselle & Sklar P L L, November 16, 1999: US05986376 (12 worldwide citation)

A brushless DC motor comprises a rotor (20) and a stator (22) having confronting surfaces. Permanent magnets (M) are provided at one of the confronting surfaces, the magnets being equally angularly spaced around an axis (A--A) of rotation of the rotor such that each magnet occupies part of a respect ...