Abstract: An armature for an electric motor comprises a winding having connector portions and a plurality of combined commutator segments and terminals. The terminals each have at least one slot which straddles and grips a respective connector portion to electrically connect the connector portion to a commutator segment. A base supports the commutator segments and a separate terminal support has a plurality of housings locating the terminals. By making the base separate to the terminal support, the armature may be wound with only the terminal support in position, the base being added afterwards, thus giving more room during winding. In a preferred embodiment, the support is formed of thermoplastics material, e.g. thermosoftening nylon, so that it is able to flex during insertion of the terminals and the base is of a material which will withstand higher temperatures, e.g. thermosetting plastics material or anodized aluminium.

Abstract: The connector, for example, is in the form of a terminal portion of a commutator segment and has two overlying parts. Each part is provided with a slot open at one end and the two slots are arranged so as to be only partly in register with one another so that the resulting slot in the terminal portion is narrower than each of the slots in the two overlying parts and is open at one end for receiving and gripping an armature winding portion. Non-aligned regions (as considered in a direction perpendicular to the plane of each overlying part) bordering the slots of the two overlying parts are offset, e.g. part sheared, out of the plane of the respective part towards the other part.

Abstract: A device for connecting a wire to a terminal of an electric motor comprises a planar portion having means for gripping a terminal. A slot is formed in the planar portion and straddles and grips a core of the wire, thus electrically connecting the wire to the terminal. The wire is held between a support and a clamping portion on the device.

Abstract: In an electric motor having a commutator, when a brush wears the associated brushleaf carrying the brush may snag in gap between commutator segments of the commutator, the rotating commutator dragging a bushleaf around into electrical contact with the other brushleaf. To prevent electrical contact being made directly, or via a common commutator segment, a stop is integrally formed with a holder carrying the brushleaves to limit the movement of the brushleaf.

Abstract: An electric motor has a can-like casing and an end cap. Brushgear is mounted on a frame prior to insertion into the motor. The frame holds the brushes of the brush gear away from a commutator of the motor by means of resilient arms which engage the brush gear. As the frame is inserted into the motor the arms come against a post which bends the arms to disengage them from the brush arms so that the brushes settle onto the commutator.

Abstract: A commutator comprises a commutator base, a plurality of commutator segments, and means securing the segments on the base. Each segment has an integral terminal provided with a slot which is open at one end for receiving a connector portion of an armature winding and which is arranged so as in use to straddle and grip the connector portion to electrically connect the commutator segment to the armature winding. The commutator is pre-assembled in that the segments and the commutator base are formed as a unit prior to mounting the commutator on the armature of a motor and can be connected to an armature winding by a mechanical connection without the application of heat.

Abstract: A terminal in an electric motor comprises a generally flat portion in a shallow recess in an outer wall of the motor housing for forming a touch contact with a power supply, and a U-shaped portion housed in a recess for receiving a terminal on a supply lead wire. The U-shaped portion may have a bifurcated arm for receiving a tinned wire lead.

Abstract: A resistor ring, typically a varistor, is clamped in intimate contact with terminals of a commutator using a clip-on plastic clamp having a plurality of shock-absorbing spring fingers, thus avoiding the application of heat which could damage the resistor ring.

Abstract: The motor has a plastic holding member which is a sliding fit in a casing of the motor and which supports at least one pair of segment magnets and brush gear for the motor in a fixed angular position relative to one another.

Abstract: In a fractional horsepower DC motor, wire of an armature coil is connected to a commutator segment by hot forging a tang of the segment onto the wire to grip it. A piece of solder is positioned adjacent the wire and tang during forging to coat the wire during forging and fill in cavities between the wire and tang, thus enhancing the electrical and mechanical connection.

Abstract: A d.c. electric motor has an oil collector located fast on a motor shaft, between a lubricated bearing and a commutator. Collector is of rubber and forms an oil tight seal with the motor shaft so that oil will migrate into a ring portion where the centrifugal force of the rotating motor will retain the oil in the ring. Preferably the collector has an oleophobic coating thereon.

Abstract: An armature comprises a winding having a connector portion coated with insulation, an armature termination, such as a commutator segment, and a support on which the termination is mounted. The termination has an integral terminal provided with a slot which straddles and grips the connector portion of the winding. The slot has an open end through which the winding is drawn after the termination has been mounted on the support. During an armature winding operation, two cutting edges cut through the insulation of the connector portion as it is drawn into the slot to establish electrical contact between the connector portion and the terminal.

Abstract: A cylindrical outer surface of a commutator is formed with circumferencially extending striations separated by sharp-edged ridges which bite into the abutting surfaces of the brushes engaging the commutator to improve electrical conductivity and reduce static mechanical friction. These striations and the ridges may extend helically so that, on relative movement between the commutator and the brushes, the abutting surfaces of the brushes are scoured. There is also a tendency for the brushes to be moved axially of the commutator, against the restoring force provided by the brush leaf, until this restoring force rises sufficiently to cause the brush to return towards its original axial position so that the surfaces of the brushes and the commutator scrape against each other so as to present fresh surfaces for abutment.

Abstract: An electric motor and gearbox unit, wherein the gearbox comprises a casing having an integral bearing support for the motor shaft and an epicyclic gear train within the casing, the output shaft of the gearbox being precisely aligned with the motor shaft. The gearbox can be symmetrically designed with respect to the motor axis so that a fan mounted on the motor shaft can create a symmetrical flow of cooling air over the gearbox casing and into the motor. Preferably, the epicyclic gear train comprises a sun gear on the motor shaft, a ring gear integral with the gearbox casing, and a plurality of planet gears that mesh with the sun gear and the ring gear and which are each mounted for rotation with respect to a planet carrier connected to the output shaft of the gearbox. The planet carrier has to be provided with a number of holes, one being a central hole for receiving the output shaft of the gearbox and the others being for receiving stub axles for mounting the planet gears.

Abstract: A direct current electric motor comprises a cylindrical casing of electrically conductive material, a stator magnet or magnets and a wound rotor, provided with a commutator, accommodated in the casing, an end cap in one end of the casing, and brush holding devices supported by the end cap. The brush holding devices have terminals which extend through the end cap for connection to an electric supply. A recess is provided in the end cap so as to extend between one of the terminals and the casing and a portion of the casing has been deformed so as to extend into the recess and make electrical contact with the one terminal.

Abstract: A solderless electrical connection between a wire and an electrical contact forming part of a permanent magnet motor. The motor includes a generally U-shaped motor frame that defines an open volume within which is mounted a plastic spacer or insert and a pair of opposed permanent magnets and that surround a rotating armature. One end of the armature terminates in a shaft which is received within a bushing that is mounted at the center of the planar central portion. The other end of the armature terminates in a shaft. Next to the armature and mounted on the shaft is a commutator. The shaft passes through a metallic bushing that is defined as part of a non-conductive insert which mates with the motor frame. Also mounted on the non-conductive member are a pair of brush assemblies. Each brush assembly basically consists of a pair of planar, opposed parallel legs that are joined together by a planar portion.

Abstract: There is disclosed an armature for an electrical device having an armature winding electrically connected to an armature termination, the armature being connectable to an external circuit by the termination. The armature also has a housing in which a portion of the armature winding is located and in which the termination includes a terminal having a configuration for establishing and maintaining electrical contact between the terminal and the said winding portion while retaining the terminal and the said winding portion within the housing.

Abstract: A d.c. electric motor has a permanent magnet stator and a wound rotor both mounted within a body. An end cover is fixed to the body and carries a thermal switch which is disposed inside the body adjacent to the windings and controls the supply current to the motor.