Abstract: Apparatus for visually indicating a worn brush condition for carbon brushes arranged in a gang-type brush holder. A strip of red Teflon tape, or other distinctive marking, is positioned on the linear spring having a coiled top portion which biases the brush into contact with the collector ring. As the brush wears down, the marking on the spring becomes visible as the spring coils more and more. The tape is positioned on the spring such that, when the exposed top portion of the spring shows completely red (i.e., the color of the marking), it is indicated to the operator that a worn brush is to be replaced.

Abstract: In a unitary bifurcated brush holder for a small electric motor, a pair of coplanar terminal tabs, each axially spaced and laterally offset from the brush holder sleeve, extend axially of the motor for direct plug-in engagement, in assembly operation, with terminals at the commutator end of a stator assembly. The brush holder is made from a single sheet metal stamping. The terminal tabs are carried at the end of a support arm extending from a wall of the brush holder sleeve. In assembly, the brush holder is mounted in an insulator which includes support bosses for engaging and augmenting the support of the rear end of the terminal tabs.

Abstract: A worn brush detector 43 for an electric generator. The worn brush detector 43 comprises a contactor strip 55 of electrically-conductive material secured to and insulated from a brush holder 28, the contactor strip 55 having a plurality of fingers 52 projecting downward from the strip 55 and generally perpendicular thereto, the fingers 52 being disposed adjacent to a hole 62 in the brush holder 28 and electrically insulated therefrom. An electrically insulated knob 61 on the opposite end of the fingers 52 projects through the hole 62 such that when a brush 25 is inserted into the holder 28 the corresponding finger 52 is pushed away from the holder by the knob 61 contacting the brush 25. When one of the brushes 25 has worn down a predetermined amount the brush 25 is disengaged from the knob 61 so that the corresponding finger 52 is caused to contact the holder 28 to generate an electrical signal.

Abstract: An apparatus for detecting the wear of a motor brush includes a spring that biases the brush towards an extended position. A portion of the spring moves along a path towards the extended position as the brush wears, wherein the spring portion makes mechanical contact with a portion of an electrical signal generating device that is disposed in the path to indicate a given amount of brush wear has occurred.

Abstract: Brush-holder plate, for mounting brush holders so that radially inwardly spring-biased brushes are locked in a radially outwardly retracted position to permit axial insertion of a commutator during the assembly of an electric motor. The plate has a first portion (1), for supporting brush holders (2, 3), and a retractable locking device for locking the brushes (12, 13) in the retracted position in the brush holders (2, 3). The locking device (4) includes a locking member (10) having branches (8, 9) extending through corresponding orifices (21, 22) of a second portion (6) of the brush-holder plate axially offset relative to the first portion (1).

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 brush assembly for a commutator type electrical machine includes a biasing spring for biasing a carbon brush toward a commutator. The brush assembly also includes a brush guide having a passageway portion formed to guide the carbon brush. A spring retainer is slidingly received within the brush guide and is disposed between the carbon brush and the biasing spring. An enlarged portion of the spring retainer cooperates with an annular shoulder formed within the brush guide to form a stop surface to limit rectilinear movement of the spring retainer within the brush guide and consequently the biasing spring when the brush is substantially worn out.

Abstract: A brush holder assembly which utilizes an insulated brush card and a bridge means to define a receiving aperture for a brush element. A pair of legs and a connecting element serve to define the bridge means and a constant force spring is retained by the legs so that as the brush is received within the aperture, the spring will partially uncoil and the uncoiled portion of the spring will conform to the profile of the brush. The bridge means also includes a retention mechanism by which the brush may be held in an assembled position prior to its installation into a motor or generator unit.

Abstract: For easily assembling an electric motor a locking lug is formed onto the brush support plate. In an assembly position the ratchet lug of said locking lug engages a cavity of the brush and keeps it at a distance from the commutator so that the commutator can easily be installed between the brushes. In order to release the arrest of the brushes during the assembly a releasing part of the locking lug projects into a recess in the housing cover. This arrangement is easy to manufacture and reduced the number of assembly steps.In a second embodiment the releasing part of the locking lug lies above the front side of the housing cover and projects into a recess in the housing cover lid.

Abstract: A brush holder assembly for a commutator type electric motor includes a substantially circular base plate of insulating material having a central aperture for receiving the motor commutator. The base plate includes a pair of brush holders for supporting brushes in operative relation to the commutator. A pair of conductive members are embedded in the base plate. Each conductive member has a brush holder mounting portion exposed on both sides of the base plate and a connecting terminal for electrical connection to the corresponding terminal of the stator coils. Power connecting means is provided on the base plate for electrically connecting the terminals of the stator coils to an electrical power source.

Abstract: A miniature motor having brushgear comprising brush arms with sliding parts on the tips thereof, terminals and brush bases; the brush bases being supported by a motor case cover plate, when the terminals are inserted in brush holes provided on the motor case cover plate; the sliding parts being brought into sliding contact with a commutator by the resiliency thereof, and characterized in that a flexible photo-setting resin having similar resiliency to the resiliency of vibration-damping rubber is applied to the brush arms to prevent the brushes from unwantedly vibrating during rotation of the commutator.

Abstract: The brush holder comprises an electrically insulating body having a pair of apertures through which extend first and second brushes, which are movable by means of a single resilient member acting simultaneously on both brushes. This solution enables the wear on the brushes to be reduced significantly, particularly on the negative brush which normally tends to be worn away more rapidly.

Abstract: The wear upon at least one of several carbon brushes in a brush holder is monitored by a lever one arm of which is biased against the rear end face of a selected brush by a spring and another arm of which actuates a microswitch in response to a predetermined amount of wear upon the brush as a result of engagement with a commutator or a slip ring, namely in response to a predetermined angular displacement of the lever from a starting position which is assumed by the lever when its first arm engages a freshly inserted brush.

Abstract: A long-life motor brush holder which significantly minimizes contact of the coil portions of a ribbon spring with the holder and consequently reduces friction drag; the arrangement is such that at least two cylindrical surfaces forming part of the brush holder serve as line contact supports for each of the respective coil portions of the ribbon spring so as to produce minimal contact, the spring including a middle portion for residually engaging the brush to urge it against the motor commutator.

Abstract: Brush rigging for a dynamoelectric machine such as an electric cranking motor for cranking an internal combustion engine. A support carries a plurality of radially extending brush holders each of which slidably supports a brush. The brushes are urged radially inwardly by an elastomeric band that is formed of electrical insulating material. The band directly engages the outer ends of the brushes and a plurality of pins that are carried by the support. The pins are located between pairs of brush holders.

Abstract: Each brush of a wound rotor type electric motor is mounted in a conducting formed-metal tube having an integral tab that is provided with a narrow slit having an enlarged mouth. The latter faces the commutator that is carried by the wound rotor and, as the tube and its assembled brush are moved radially inward to their operating positions, initially receives one end of magnet wire that forms a stator winding. As the stator winding and its associated field stack are moved into operative position with respect to other elements of the stator an indexing formation of the stator positions the wire end for engagement with the tab of the tube. With the tube in its operating position, the wire end is disposed within the narrow slit and is clamped between the tab jaws that are on opposite sides of the slit.

Abstract: An optical device for detecting a condition of a carbon brush in a drive unit includes lightguides disposed in vicinity with the carbon brush yet out of contact with the carbon brush and having a device for monitoring wear of the carbon brush, and a device for triggering a warning signal when the carbon brush has reached a predetermined residual length.

Abstract: An improved brush gear assembly for use in a miniature motor. The brush gear assembly is mounted within the interior of the end cap of the motor and basically consists of three parts: a terminal element or fitting, a brush leaf element, and a brush. The terminal element consists of a generally planar brass part, a major part of which is defined as an elongated rectangular portion. One end of the rectangular portion defines a bending end. Near the bending end are disposed three staggered projections arranged generally in line adjacent to a transverse bending line formed on the rectangular portion. The leaf spring is formed from a substantially elongated planar copper strip, which has one end terminating in a bending portion. The remainder of the strip constitutes a spring portion and terminates at its other end in a brush receiving portion, which is reinforced by bending the sides in an upward direction.

Abstract: A brush wear indicator for a dynamoelectric machine, such as a direct current motor, comprises a fiber optic conductor coupling an emitter and a detector. The fiber optic conductor is fed into a brush holder where it is supported by a spring holder to which is attached a coiled biasing spring. The fiber optic conductor includes a region of separation where an element actuated by the biasing spring operates to complete or interrupt a light path between the exposed ends of the conductor at the separation. In one embodiment, an angulated tab secured to the spring operates as a shutter to move in and out of the spring holder to complete or interrupt the light path, while in a second embodiment, a rubber flexible diaphragm having an inwardly projecting body portion is actuated by the spring, by moving in and out of said region of separation to complete or interrupt the light path.

Abstract: A brush wear detector and indicator for the brush elements contacting the rotating commutator or slip rings of a dynamoelectric machine includes, in addition to a self winding bias spring located on the brush holder for applying force to the brush assembly, a permanent magnet, located either on a brush element or the bias spring, and a reed switch located on the brush holder adjacent the assembly. The magnet moves inwardly as the brush element wears and actuates the read switch at a point indicative of a worn condition. Activation of the reed switch causes an indicator such as a lamp to become energized, signalling a need for brush element replacement.

Abstract: A brush wear detector assembly for the brushes contacting the rotating commutator or slip rings of a dynamoelectric machine includes a light interruptor member located in a housing attached to the brush holder with the light interruptor being biased by a compression spring which operates to push the light interruptor against the side of the brush. The light interruptor includes an aperture, or other discontinuity, which is located adjacent the separation of a fiber optic conductor. During a usable condition of the brush, a light path is completed through the aperture between the exposed ends of the fiber optic conductor; however, for a worn condition of the brush, it is forced laterally into the brush holder behind the end of the brush causing the light path to be interrupted whereupon a signal indicative of a worn condition of the brush is generated. Alternatively, the aperture or conductor positioning could be such that at worn brush condition a light path is established.

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: A brush assembly for use in a homopolar dynamoelectric machine includes a plurality of contact elements extending into slots of a movable brush holder. Resilient tubular members extend through each of the brush holder slots and lie adjacent to the bottom of the slots. The brush holder is movable with respect to a brush box that includes an array of openings positioned to receive the contact elements. An actuating rod for moving the brush holder with respect to the brush box and projections, on opposite sides of each slot, for retaining the contact elements within the brush holder slots are also provided. When the brush holder is lowered such that the contact elements make sliding electrical contact with the surface of a rotating rotor of the homopolar machine, the resilient tubular members provide a spring force which keeps the contact elements in intimate sliding contact with the rotor surface.

Abstract: A homopolar dynamoelectric machine is provided with a stator structure having an interior surface defining an internal space for receiving a generally cylindrical rotor which is mounted for rotation with respect to the stator structure. A plurality of brush assemblies are positioned between the stator interior surface and an exterior surface of the rotor and are capable of making sliding electrical contact with the rotor exterior surface. Each of the brush assemblies is connected by way of a brush drive rod to a brush actuator which is positioned on an external surface of the stator structure, to control radial displacement of the brushes. By mounting the brush actuators on an external stator surface, a reduction in stator size and weight is achieved.

Abstract: A hammer brush holder assembly can be easily fabricated and assembled by robot automation using only a few simple steps. The brush holder has at least two brush support arms swivel-mounted at one end in a brush rocker and pressed against a commutator by a tension spring via the brushes which are held at the other end of the brush rocker. The brush support arms with sleeve-shaped ends can be slipped axially onto lugs molded in an axial fashion to the brush rocker and locked in place. Both brush support arms are connected as parts of a single-piece plastic injection-molded component with an integral breakaway bridge segment which holds both brush support arms to a preselected mutual spacing. The breakaway bridge segment can be eliminated after installation of the hammer brush support assembly in the commutator motor.

Abstract: A brush assembly for an electrical machine has a holder having a pair of generally parallel side walls having confronting inner faces, a guide wall extending along and between the inner faces and in turn having an inner face defining with the faces of the side walls a passage extending in a longitudinal direction and having a longitudinally forwardly open front end, and an angled surface adjacent the front end. The brush in the passage has a longitudinal guide face longitudinally slidable on the inner face of the guide wall but out of contact with the side walls, an opposite longitudinal face turned away from the guide wall, and axially opposite front and rear ends. A coil spring has a coiled part engaged between the angled surface and the opposite brush face at the front end of the brush to transversely urge the brush against the inner face of the guide wall and a free end extending longitudinally back along the opposite face longitudinally past the rear end of the brush.

Abstract: A brush holder adapted for automatic assembly having a simplified construction and reduced cost. The brush holder is composed of a generally U-shaped holder box having an opening extending from a top end thereof along one side of the box, and a holder plate covering the opening. The holder plate has a recess for receiving the brush therein, and a stop for preventing movement of the brush through the opening of the holder box when retained by the stop. When the brush is to be mounted on a motor casing or the like, a protrusion of the motor casing is extended through a through-hole in the holder plate, thereby releasing the brush from engagement with the brush stop and permitting it to protrude through the hole in the top end of the box.

Abstract: A brush holder assembly for use in an electric motor or generator has an insulating ring one side of which carries a set of several equidistant carriers for brushes which are biased in the radial direction of the ring to bear against a slip ring or against a commutator. Each carrier is radially adjustably secured to the ring by two screws or bolts and nuts whose shanks extend through two elongated slots provided in a flange-like extension of the carrier. Each extension has a tongue extending into a radial groove in the one side of the ring. The axial position of each carrier relative to the ring can be changed by inserting one or more shims between the extension and the ring.

Abstract: A brush-holder for the disc commutator of rotating electric machines, in which axially-disposed brushes are maintained in abutment against the disc commutator by a spring constituted by two windings housed in a cavity located in the brush-holder opposite the brush guides. The two windings are separated by a median loop which engages elastically behind a retaining catch. The invention is particularly applicable to electric starters for internal combustion engines.

Abstract: An electric motor adapted to be assembled automatically with the minimum of manual handling has a brush box sub-assembly having a brush box with two opposed side walls and containing a brush. The two opposed side walls are stressed to grip and hold the brush against movement, the brush being released for movement in the brush box by separating sufficiently the opposed side walls upon insertion in the electric motor. Preferably, the brush box has a slot between the opposed side walls and a member in the motor is forced into the slot to separate the side walls. In assembling the motor, its stator is located on an end cap, the rotor inserted into the stator, and then the distance measured between an end face of the stator and a location on the shaft of the rotor; subsequently a shaft bearing in that end cap is pressed inwards an amount related to the measured distance to determine the end float of the shaft.

Abstract: An axial-type homopolar motor having high density, high current fiber brush ollectors affording efficient, low contact resistance and low operating temperatures. The collectors include a ring of concentric rows of brushes in equally spaced beveled holes soldered in place using a fixture for heating the ring to just below the solder melting point and a soldering iron for the local application of additional heat at each brush. Prior to soldering, an oxide film is formed on the surfaces of the brushes and ring, and the bevels are burnished to form a "wetting" surface. Flux applied with the solder at each bevel removes to an effective soldering depth the oxide film on the brushes and the holes.

Abstract: An electric motor with commutator having more than two poles comprises two brushes and two brush holders placed 90.degree. in relation to one another and mounted on an independent brush holder washer. To hold the washer centered during assembly, a pin 7 is provided, fastened to the washer approximately on the bisector of the angle formed by the two brushes, and in opposition to these brushes. Under the pressure of brushes 3, pin 7 rests along a generatrix of commutator 5 to stop washer 1 in a position almost centered in relation to the commutator, which then facilitates mounting of the flange constituting the cover and bearing of the electric motor.

Abstract: Brushgear having L-shaped brush arms, each consisting of a terminal strip and a commutator contactor strip, both being joined into one piece by lapping one on another and crimping a plurality of projections formed on the terminal or commutator contactor strip. The terminal and commutator contactor strips are made of materials suitable for each thereof. The brush arms are inserted into the grooves of brush holders provided on a case cover of a motor case and firmly held in position.

Abstract: A brush holder for an electric motor having a commutator. The brush holder includes a simple flat plate (10) cut or stamped to provide slots (20) for sliding of the brushes (12) and openings (26) for holding the brush springs (14). The springs (14) normally engage the ends of the associated brushes (12) to bias them inwardly towards the motor commutator. When the brushes are retracted, the springs engage the sides of the brushes to lock the brushes in the slots.

Abstract: A carbon brush assembly comprises a brush box having a slit along one side thereof, and a carbon brush slidably mounted in the brush box with a spring connected between the brush box and the brush to resiliently urge the brush outwardly. An electrically conductive pin is inserted in a transverse bore in the brush and extends through the slit for movement therealong. A brush lead is electrically connected to the pin and a stop associated with the slit adjacent the outer end thereof. The stop forms a closed end of the slit for limiting movement of the pin therealong under the influence of the spring, and so retaining the pin in the slot when said brush wears out. Preferably, the brush is formed with breaking incisions in its sides adjacent the pin to enable the protruding end of the brush to break off and interrupt electrical connection with a commutator when the brush has worn to the end of its useful life.

Abstract: A brush holder assembly providing longer brush life and easy brush replacement is disclosed. The assembly uses a removeable spring bracket to extend a double coil constant force extension spring straddling a brush. The bracket, straddling the spring and brush, is inserted into a brush holder, whereupon it slideably engages the coils of the extension spring, causing it to extend. The bracket is removeable from the holder so that the extension spring and brush can be removed to replace a worn or broken brush.

Abstract: A high-energy, high-current homopolar generator pulsed power supply system that is compact and field portable. The power supply system includes a hompolar generator (HPG), an auxiliary supply and drive system, both mounted on a skid frame, and a control system coupled to the HPG and drive system. The homopolar generator has a split rotor with insulation between the halves and a recess in the periphery. A stator ring and field coil, for producing a magnetic field through which the rotor halves make two simultaneous voltage-generating passes, are disposed within the recess in the rotor. Air-actuated brush mechanisms inside and outside the recess contact surfaces of the rotor and collect discharge current. The auxiliary supply and drive system includes a motoring system comprising hydraulic motors for driving the HPG to speed, a bearing lubrication system, a generator for energizing the field coil, and a brush actuator air supply system, all of which are driven by a prime mover.

Abstract: A brush wear indicator contact and terminal assembly having a high pressure-per-unit contactor that is formed on a first surface of the plate. A conductor for a brush wear indicator circuit is bonded to the contact plate by a high temperature resistant solder or brazing material and the contact plate is bonded to the surface of the dielectric sheet, which electrically isolates the contact from the spring when the spring is in an extended condition. By the method of the invention, a brush wear indicator contact and terminal assembly is made by adhering a sheet of dielectric material to a brush follower spring with a coating of permanently flexible adhesive, and by bonding a conductor for a brush wear indicator circuit to a contact plate having a contactor ridge on one opposite surface thereof.

Abstract: The motor housing comprises a cup-shaped ferromagnetic part having an open end and an axial end plate of ferromagnetic material closing off the open end to form a motor housing of rectangular cross-section when viewed in longitudinal section. A generally disk-shaped rpm-signal generating structure is mounted interiorly of the motor housing, coaxial with the rotor axis, at one axial end of the housing, and just inward of a wall of the motor housing which forms part of the flux-conducting magnet system of the motor, whereby such wall shields the rpm-signal generating structure at least against electromagnetic interference originating exteriorly of the motor housing. The motor comprises slip rings or commutator segments on whose surfaces stationary brushes ride.

Abstract: An electric motor adapted to be assembled automatically with the minimum of manual handling has a brush box sub-assembly having a brush box with two opposed side walls and containing a brush. The two opposed side walls are stressed to grip and hold the brush against movement, the brush being released for movement in the brush box by separating sufficiently the opposed side walls upon insertion in the electric motor. Preferably, the brush box has a slot between the opposed side walls and a member in the motor is forced into the slot to separate the side walls. In assembling the motor, its stator is located on an end cap, the rotor inserted into the stator, and then the distance measured between an end face of the stator and a location on the shaft of the rotor, subsequently a shaft bearing in that end cap is pressed inwards an amount related to the measured distance to determine the end float of the shaft.

Abstract: Brushgear having brushes, each comprising a terminal and a brush arm, both made of electrically conductive metal strips and joined together into one piece, the brushes being held in position on a side plate of a motor case, made of a synthetic resin, by being inserted into terminal holes provided on the motor case side plate. The terminal and brush arm of each brush are made of different metal strips and a terminal strip of the terminal and a brush strip of the brush arm are mechanically joined together into one piece by folding joining members provided integrally with the terminal strip in such a manner as to wrap around an end of the brush strip provided on the brush arm. The joined portion of the terminal and brush strips are inserted into the terminal hole to hold the brush in position on the motor case side plate.

Abstract: A brush wear detector comprised of an L-shaped leaf spring having the outer end of its longer leg mounted on a first insulating member in fixed relationship to a spring support for a self-winding, brush-biasing spring. A second dielectric member is secured to the leaf spring between the ends thereof and projects outward from the leaf spring into engagement with an uncoiled section of a brush-biasing spring. The free end of the leaf spring is held away from engagement with the brush-biasing spring support, thereby being electrically isolated from it, when a new brush is mounted in operating position under the brush-biasing spring. When the brush becomes worn a pre-determined amount the brush-biasing spring moves in a direction away from the second dielectric member and so enables the leaf spring to force its free end into electrically conducting engagement with the electrically energized spring support.

Abstract: This invention relates to a brush holder for a rotary electric apparatus comprising: a holder body having a brush frame for slidably holding a brush, a brush retainer pivotally secured to a holder arm attached to the holder body through a pin, a spring provided between the holder body and the brush retainer, a stopper mounted on the holder body for stopping the movement of the brush retainer at a predetermined position, and a contacting piece mounted on the stopper being electrically insulated from said holder body and positioned so that it comes into electromechanical contact with the brush retainer when the brush reaches the wearing limit.

Abstract: A brush holding device of a rectangular shape, comprising a brush holding plate, made of a resilient material, having formed bent pieces on both side edges thereof, the brush holding plate having a brush insert hole on the edges of which lanced and raised pieces are provided. A brush is held in position by the aid of resiliency caused by the deformation of the bent pieces provided on both side edges of the brush holding plate when inserting the brush into the brush inserting hole.

Abstract: A brush wear indicator contact and terminal assembly having a high pressure-per-unit contactor that is formed on a first surface of the plate. A conductor for a brush wear indicator circuit is bonded to the contact plate by a high temperature resistant solder or brazing material and the contact plate is bonded to the surface of the dielectric sheet, which electrically isolates the contact from the spring when the spring is in an extended condition. By the method of the invention, a brush wear indicator contact and terminal assembly is made by adhering a sheet of dielectric material to a brush follower spring with a coating of permanently flexible adhesive, and by bonding a conductor for a brush wear indicator circuit to a contact plate having a contactor ridge on one opposite surface thereof.

Abstract: A structure for retaining a cartridge brush holder in a dynamoelectric machine having a tubular frame member having a smooth curved inner surface and an outer surface is shown, including an aperture adapted to receive a generally cylindrical body of said cartridge brush holders through the frame member, the body of the cartridge brush holder being installed through the aperture with its flange adjacent the outer surface. A plano-convex member having a first convex surface and a second flat surface and having a bore therethrough receives the body of the cartridge bursh holder. A spring washer is placed over the cylindrical body of the brush holder, and retained by a retaining ring means pressed over the cylindrical body of the brush holder adjacent the spring washer to compress the spring washer to retain the brush holder in the tubular frame member.

Abstract: A brush holder for dynamo-electric machine has the following parts: a brush making sliding contact with the surface of a rotary collector; a stationary holder part fixed to the stationary part of the dynamo-electric machine opposite to the collector; and a detachable holder part detachably secured to the stationary holder part and holding the brush when separated from the stationary holder part, the detachable holder part being provided with a retainer that clamps the brush when the detachable holder part is separated from the stationary holder part and unclamps the brush when it is attached to the stationary holder part, the brush clamping portion and the portion of the retainer therearound being coated with a coating film of a material having a friction coefficient smaller than the material of the retainer. This arrangement obviates various unfavorable phenomena such as jumping of the brush, sparking on the sliding surface, cracking in the brush and so forth.

Abstract: An electrical machine having an armature that is rotatable in a stator. The armature has a winding that is energized via a commutator or via slip rings cooperating with brushes. A holding plate is provided on which the brushes are held and which is supported freely shiftable in the direction of the axis of rotation of the machine, but circumferentially immovable. The holding plate butts against a part that is supported axially immovable on the shaft of the armature, preferably a bearing. Spring means acting between the holding plate and an adjacent side plate of the stator or housing serves to bias the holding plate in an axial direction. The part against which the holding plate butts, lies preferably in or near the plane of the holding plate.

Abstract: A brush holding device for holding carbon brushes in sliding contact with slip rings of an alternator. The device has a brush holder formed by an insertion molding integrally with terminal plates. The brush holder has a pair of brush chambers for movably receiving the carbon brushes and a pair of pig tail chambers accommodating pig tails through which the carbon brushes are electrically connected to the terminal plates. The carbon brushes are resiliently biased into contact with the slip rings by means of coiled springs acting between the radially outer ends of the carbon brushes and the radially outer walls of the brush receiving chambers. The pig tails are extended into adjacent brush chambers through slits formed in the walls separating the pig tail chambers from associated brush chambers and are connected to the carbon brushes at lateral sides of the latter.