541results about How to "Improve motor efficiency" patented technology

A cooling device for cooling a heat-generating component includes a circulating passage arranged to have coolant circulate therein, a centrifugal pump including a first case made of metallic material, a second case made of resin material, and an impeller accommodated in the pump chamber, and a radiator provided at the circulating passage and being operable to release heat from the coolant. The first case has a surface arranged to contact the heat-generating component. The second case forms a pump chamber between the first case and the second case. The pump chamber stores the coolant therein. The impeller includes open-type vanes arranged to pressurize the coolant as to have the coolant flow through the circulating passage. The cooling device has a high cooling efficiency as well as a high operating efficiency of the motor while having a simple construction and a small overall size and a small thickness.

A method for driving a load by using an output stage amplifier in full bridge configuration whose supply is modulated by means of a fast switching power converter, controlled in order to maintain the stage's output common mode at its minimum voltage, is presented. The modulation of the switching power converter output is obtained by a feedback control system regulating directly the voltage of the bridge output stage terminals. This bridge unipolar class H stage allows driving the load with high accuracy and improved efficiency without introducing switching noise and EMI at the load terminals typical of PWM driving. This method can be applied with the same benefits to class AB, pseudo class AB or to class A output stages. When this method is associated with an imposed current driving approach and with a current oversampling digital to analog converter the resulting advantages are very significant for accurate motor control applications.

A rotor-stator structure for electrodynamic machinery is disclosed to, among other things, minimize magnetic flux path lengths and to eliminate back-iron for increasing torque and/or efficiency per unit size (or unit weight) and for reducing manufacturing costs. In one embodiment, an exemplary rotor-stator structure can comprise a shaft defining an axis of rotation, and a rotor on which at least two magnets are mounted on the shaft. The two magnets can be cylindrical or conical magnets having magnetic surfaces that confront air gaps. In some embodiments, substantially straight field pole members can be arranged coaxially and have flux interaction surfaces formed at both ends of those field poles. Those surfaces are located adjacent to the confronting magnetic surfaces to define functioning air gaps, which are generally curved in shape.

An electric fuel pump is disclosed which includes a pump portion, a motor portion, a housing, and a fuel passage. The pump portion pressurizes fuel. The motor portion drives the pump portion. The motor portion includes a rotor with a rotating shaft and a stator that surrounds an outer periphery of the rotor. The housing surrounds, at least, an outer periphery of the stator of the motor portion. The fuel passage, through which the fuel pressurized by the pump portion passes the motor portion, is made up of a clearance between the outer periphery of the stator of the motor portion and an inner periphery of the housing. The clearance extends, at least, in the axial direction of the rotating shaft of the rotor of the motor portion.

A regenerating braking system is provided, which includes: a synchronous motor with field coil excitation including a cylindrical stator coil, an inverter electrically connected to the stator coil, a battery electrically connected to the inverter, a rotor coil provided in an internal space of the stator coil, a two-way switch electrically connected to the rotor coil, and a capacitor electrically connected to the two-way switch; and a controller, wherein when the first differential calculus of acceleration of a load on the synchronous motor becomes negative, the controller stores regenerative power regenerated in the rotor coil from the stator coil, in the capacitor through the two-way switch, and wherein the controller supplies the regenerative power stored in the capacitor to the rotor coil through the two-way switch.

A BLDC motor assembly and method for manufacturing same is disclosed. The motor has a housing, a shaft supported for rotation within the housing, a stator disposed within the housing for generating an electro-magnetic field, a rotor operatively coupled to the shaft and disposed for powered rotation within the stator in response to the electro-magnetic field, at least one temperature sensitive electronic device (TSED) disposed within the housing and electrically connected to the stator for controlling or measuring an aspect of the electro-magnetic field, and a fuel resistant and electrically insulated polymeric material encapsulating the TSED so that the TSED is protected from adverse temperature and chemical agents without the need for a separate internal container or a pre-potting operating. The TSED, which may be carried on a printed circuit board within the housing, is thus overmolded with polymeric material so that the polymeric material fills, or substantially fills, a space within the housing. Not only is the cost and weight associated with a prior art dedicated container for the electronics eliminated, but this invention allows greater design freedom in the location or placement of the various electrical devices within the housing for better motor efficiency and/or protection.

The electric machine of the present invention comprises a first coil group containing a plurality of coils and a magnet group. The first coil group is classified into M phase sub coil groups, with the coils of the sub coil groups aligned one at a time in sequence at a specified sub coil group interval Dc from the first phase sub coil group to the M-th phase sub coil group. A sub coil group interval Dc is set to a value of K/M times a magnetic pole pitch Pm (K is a positive integer excluding an integral multiple of M) where the distance corresponding to an electrical angle of π is defined as the magnetic pole pitch Pm. The adjacent sub coil groups are driven at a (K/M)π phase difference. Each coil have substantially no magnetic material core.

A method of operating a brushless direct current motor is provided that generates a rotor position dependent pulse width modulation waveform. The waveform can improve motor efficiency and reduce torque variation.

Provided is a drive control device for a standby four-wheel drive vehicle having primary drive wheels coupled to a drive source including a motor generator that generates a regenerative braking torque and a clutch device disposed between the drive source and secondary drive wheels to switch a two-wheel drive state using the primary drive wheels and a four-wheel drive state using the primary drive wheels and the secondary drive wheels, including: a transmission torque control portion that causes the clutch device to set a transmission torque between the drive source and the secondary drive wheels to zero so as to allow only the primary drive wheels to perform regenerative braking if a request braking torque of the vehicle is equal to or lower than a predetermined primary-drive-wheel regeneration limit torque during the regenerative braking by the motor generator, the transmission torque control portion causing the clutch device to generate the transmission torque between the drive source and the secondary drive wheels so as to allow the primary drive wheels and the secondary drive wheels to perform the regenerative braking if the request braking torque exceeds the primary-drive-wheel regeneration limit torque.

A hybrid-vehicle drive unit supports a motor-generator with high precision, improving the efficiency of the motor-generator, and reducing the size of the motor-generator, independent of any influence of centering precision of the crank shaft and of deformation of the torque converter. According to the invention, a motor housing is disposed between a converter housing and an internal combustion engine, and a bearing is fitted to a lateral wall provided in a front portion of the motor housing. Rotor supporting members are independently supported by the bearing. Eccentric rotation of the crank shaft resulting from explosive vibrations of the engine is counteracted by two flex plates. Owing to a predetermined clearance, one of the rotor supporting members as a separate component is free from the influence of deformation of the torque converter.

A flat-type single phase brushless direct current (BLDC) motor includes a rotor rotatably fixed to a shaft and having a permanent magnet attached to a lower side thereof; a stator plate installed below the rotor; a plurality of stator cores installed on the stator plate to face the permanent magnet, the stator cores including soft magnetic powder and arranged to be asymmetric with respect to a rotation radial direction of the rotor so as to determine a rotational direction of the rotor; and a multiplicity of coils each being wounded around corresponding one of the stator cores to form a magnetic field toward the permanent magnet.

In accordance with one exemplary embodiment, the present technique provides an electric motor having a stator core that is formed of a plurality of stator laminations and a rotor core that is formed of a plurality of rotor laminations. In the exemplary motor, the rotor laminations have mechanical and/or electrical characteristics that are different from the stator laminations. For example, the rotor laminations may have a different thickness than the stator laminations. Also, the rotor laminations may comprise a different material than the stator laminations. For example, the stator laminations may by alloyed with a certain percentage of an element, while the rotor laminations are alloyed with a different percentage of element.

An electromagnetic motor with increased torque. The motor has a rotor coil configured to generate a magnetic field. At least two stator coils are connected in series with the rotor coil. Each of the stator coils is configured to generate a respective magnetic field. The motor further includes a plurality of switches configured to generate the magnetic field in each of the respective rotor and stator coils. The switches are configured to generate the magnetic field in the stator coils such that the rotor coil rotates in response thereto. By having the rotor and stator coils connected in series, the torque of the motor is increased.

An axial flux electrical machine including a housing, a stator located within the housing, a rotatable shaft carried by the housing by means of at least a main bearing, and a rotor fixed to the shaft within the housing. Magnetic attractive forces between the rotor and the stator produce an axial thrust on the main bearing and a biasing means (preferably in the form of a spring) is arranged to urge the shaft in a direction opposite to the axial thrust so as to reduce the net load on the main bearing. This reduction in net load on the main bearing increases bearing life and improves motor efficiency.

Various embodiments of an electric motor and electronic control for an electric motor are disclosed. An exemplary electric motor comprises a single-phase brushless permanent magnet electric motor. In exemplary embodiments, the electronic motor control is configured to commutate an electric motor at a frequency other than line frequency, perform pulse width modulation, and drive the electric motor with a drive waveform that approximates the counter-electromotive force of the motor.

A treadmill roller structure comprises a motor, a gear set and a case. The motor is an out-runner motor. The power output section of the motor rotates about stationary spindle. The rotary power output section is engaged to the gear set, while the gear set is in turn engaged to the case, thus allowing the case to rotate relatively to the spindle of the motor as well. The roller structure does not require a driving belt to transfer power from the motor to the roller, thus reduces the power loss due to frictional force during power transfer through belt driving, which enhances the performance of the motor and offers a space-saving feature. In addition, the instant disclosure also provides a treadmill.

A method, apparatus, article of manufacture and system for producing a field pole member for electrodynamic machinery are disclosed to, among other things, reduce magnetic flux path lengths and to eliminate back-iron for increasing torque and/or efficiency per unit size (or unit weight) and for reducing manufacturing costs. For example, a field pole member structure can either reduce the length of magnetic flux paths or substantially straighten those paths through the field pole members, or both. In one embodiment, a method provides for the construction of field pole members for electrodynamic machines.

The present invention provides a low-iron-loss (high-efficiency) and low-cost axial gap motor that includes a high-quality soft magnetic material placed at an appropriate position, reduces torque pulsation, keeps induced voltage in the shape of a sine wave, and increases the degree of freedom in design. The axial gap motor includes a stator having stator teeth; and a rotor being opposed to the stator with a gap in an axial direction of the stator. Each of the stator teeth includes a stator tooth body, a stator tooth end joined to at least one axial-direction end of the stator tooth body, and a stator coil disposed around the stator tooth body. The stator tooth body includes a wound core comprised of a multi-layered amorphous foil strip winding. The stator tooth end is formed by a compact made of a powder magnetic core, and includes an opposed surface to the rotor. A cross-sectional area of the stator tooth end perpendicular to an axis of the amorphous foil strip winding is larger than a cross-sectional area of the stator tooth body perpendicular to the axis of the amorphous foil strip winding.