Abstract:
A P.M. d.c. motor which may utilize "brushless" commutation. The motor includes a stator assembly with a plurality of upstanding discrete spaced-apart core components formed in a circular locus generally parallel with the motor axis. Each core component includes a relatively lengthy winding association region and extending therefrom a pole piece region providing a flux interaction surface. A field winding mounted upon a bobbin is positioned over the core component at the winding association region and when excited, generates electromagnetic flux at the flux interaction surface. A permanent magnet component is carried by a rotor such that its interaction surface is adjacent to that at the pole piece region, and is spaced therefrom to define a flux working gap at a desirably lengthy working gap radius from the motor axis.
Abstract:
An object of the present invention is to provide a low cost, high performance, thin structure rotary motor for driving medium used in magnetic disk drive unit, optical disk drive unit or the like, in order to improve the productivity of terminating processing and the reliability of the coils. Magnetic materials which are divided to a plurality of blocks or divided corresponding to respective magnetic pole teeth are connected by means of thin portions. The respective magnetic pole teeth are wound continuously with wire without cutting the wire at the positions in which the thin portions are connected. When a stator is assembled, a plurality of blocks or magnetic pole teeth are disposed on a substrate by separating or bending the thin portions.
Abstract:
An electric motor including a permanent-magnet rotor having embedded magnets held in place by several segments. The embedded magnets are secured by segments including non-circular openings near their centers. Several non-magnetic, non-conductive bars extend through the non-circular openings of the segments to secure the segments in relation to the shaft. The motor is capable of producing high torque while only requiring a minimum amount of space.
Abstract:
To improve the movement precision of a synchronous linear motor, it is proposed that the front and rear end faces (11, 12) of the primary section (10) be ungrooved and not wound and bevelled in sections in such a way that the angle of inclination (.beta.) of the bevelled surfaces (11a, 12a) on the front and rear end faces (11, 12) of the primary section (10) in relation to the longitudinal axis (13) of the motor is selected according to the relation: .beta.=arctan (b/.tau..sub.p) where .beta. is the angle of inclination of the bevelled surfaces (11a, 12a) at the front and rear end faces (11, 12) of the primary section (10), b is the electrically active width of the primary section (10) and .tau..sub.p is the pitch of the poles (21, 22) of the secondary section (20).
Abstract:
An induction machine having ferromagnetic conducting material in the rotor is disclosed. The machine may be used as a motor, an alternator, a generator, or an alternator/starter. The machine includes a first stator and a second stator in a symmetrical mirrored relationship to the first stator such that a gap is defined intermediate the first and second stator. A disk-shaped rotor is disposed in the gap. The rotor is substantially comprised of ferromagnetic material electrically conducting in the radial direction and may include copper bars or rings embedded within the rotor.
Abstract:
Systems and methods for controlling a draft inducer for use with a furnace. The draft inducer includes a motor for driving a fan for inducing a draft in the furnace that causes a pressure drop across the heat exchanger of the furnace. A memory stores information including a table of predefined speed/torque values for defining a set of speed/torque curves for operating the motor. A pressure switch provides a pressure signal representative of a reference pressure across the heat exchanger and a processor determines the speed and torque of the motor when the pressure drop corresponds to the reference pressure. In response to the determined motor speed and motor torque, the processor retrieves a parameter defining at least one delta value from the memory. The processor adapts the predefined speed/torque values as a function of the delta value thereby to define the speed/torque curves corresponding to a desired pressure drop. A control circuit generates a motor control signal in response to the defined speed/torque curves to cause the motor to operate as a function of the determined motor speed and motor torque for controlling the draft induced in the combustion chamber.
Abstract:
Systems and methods for controlling a draft inducer for use with a furnace. The draft inducer includes a fan for moving combustion chamber gases for inducing a draft in the furnace combustion chamber that causes a pressure drop across a heat exchanger. The density of the gases flowing across the heat exchanger and the fan differs from a first operating state of the furnace to a second operating state of the furnace. A motor drives the fan in response to a motor control signal so that different motor speeds result as a function of the density of the gases flowing across the fan. A control circuit generates the motor control signal as a function of a first set of speed/torque curves until a speed signal indicates that the motor has reached a predetermined speed. After the speed signal indicates that the motor has reached the predetermined speed, the control circuit generates the motor control signal as a function of a second set of speed/torque curves. Thus, the motor will operate in accordance with the first speed/torque curves when the furnace is in the first operating state and in accordance with the second speed/torque curves when the furnace is in the second operating state.
Abstract:
The present invention provides a rotor for a synchronous rotary machine, having a rotor core (23) provided in its outer circumference with recesses (26), and permanent magnets (25) each fitted radially in each recess (26) so that its lower surface (25b) will be seated on the bottom surface of the recess (26). Each permanent magnet (25) and each recess (26) are formed so that gaps are formed between the inclined side surfaces (27a, 27b) of the permanent magnet (25) and the corresponding inclined side surfaces (26b, 26c) of the recess (26), and an adhesive filling up the gaps is hardened to form wedging layers (30) capable of restraining the permanent magnet (25) from being separated from the surface of the rotor core (23) by forces acting on the permanent magnet (25) to separate the permanent magnet (25) from the surface of the rotor core (23).
Abstract:
A dynamo assembly comprising a stator assembly and rotor assembly as shown. The preferred rotor assembly comprises two end caps, a single wire strand, a collector ring assembly and a plurality of laminants. The two end caps are preferably identical to one another, and oriented with the wire wrapped in two coils therearound. The laminants are supported between the two end caps, in a skewed manner. An advantageous arrangement for engagement between the collector ring assembly and wire held on the end caps is provided. A unique method of molding the collector ring assembly without internal inserts is also disclosed.
Abstract:
An improved electric propulsion motor for marine vehicles. The motor has an axial gap design with a disk-shaped rotor and two disk-shaped stators. Within the large, open diameter of the motor a sound isolation coupling is disposed between two annular plates that connect the rotor to the propeller shaft. Circumferential thrust bearings counter and distribute electrical and mechanical forces in the motor to maintain the position of the rotor relative to the stators. A journal bearing supports the rotor. Noise reduction is greatly enhanced by the implementation of staggered stators, skewed stator slots, skewed field poles and a current control system that compensates for torque pertubations that are a repeatable function of shaft angle.