Abstract: The present invention is a slip ring assembly for an automotive alternator, or other appropriate rotary electric machine, which includes at least one slip ring, a plastic body mounting the slip ring, at least one electrical terminal connected to the slip ring and supported by the body and at least one reinforcement ring. The reinforcement ring is operatively disposed on the plastic body and operatively adapted so as to strengthen the slip ring assembly against catastrophic failure resulting from loads applied to the slip ring assembly while it is under severe operating conditions. By employing such a reinforcement ring, the present slip ring assembly can be produced inexpensively with plastic bodies made from polyester and like plastics and yet still be able to withstand operating loads applied under high rotational speeds, elevated temperatures and other adverse conditions.

Abstract: A roll commutator for electric motors has a plurality of bars adjacent to one another and produced from a continuous metal section. The metal section already has projections on one of its sides before the production of the bars, which projections serve as anchoring claws after rolling up the line portions produced from the metal section. Additional tools and processing steps are not needed since it is not necessary to process the claws when manufacturing the roll commutator.

Abstract: A commutator for electric motors which is highly durable and which can be manufactured at lower cost and by a simpler method includes forming the commutator pieces on the outer periphery of the insulating resin material by providing slits between the commutator pieces. Formed on the inner periphery of the commutator pieces are a pair of engagement claws which face each other and become closer to each other in the radially inwardly extending direction. A filling space part which diminishes in the radially inwardly extending direction is formed between the pair of engagement claws, and an axial end claw which links the pair of engagement claws is formed on the axial end of the commutator piece. Furthermore, a cut part which links the filling space part is formed on the axial end claw in correspondence to the filling space part.

Abstract: A face type commutator (10) includes a hat shaped member (12) and an insulator hub (14) with an armature axis of rotation (22). The hat shaped member (12) has a plate portion (24) with a brush contact surface (26) in a plane perpendicular to the axis of rotation (22) and a cylindrical portion (16) that extends axially from the brush contact surface and defines a cavity (46). The hub (14) fills the cavity (46) and slots (42) in the cylindrical portion (16). Grooves (70) divide the plate portion (24) into a plurality of collector segments (72). A cylindrical sealing surface (76) is formed on the cylindrical portion (16) and portions of the hub (14) below the grooves (70). Tangs (30) integral with the cylindrical portion (16) below the cylindrical sealing surface (76) each have a radially extending leg portion (32) and a foot portion (34) that extends circumferentially from both sides of the leg portion to hold armature coil wires (40) on the leg portion.

Abstract: A separate slip ring unit for fitting to an alternator, especially a motor vehicle alternator, has a body of insulating material moulded over electrically conductive elements of the unit. It comprises a first cylindrical body portion with slip rings, a second body portion having elements for electrical connection to the alternator winding, and an intermediate body portion joining the first and second body portions together. The intermediate portion has two branches, including a conductive linking portion embedded in the insulating material. The second body portion comprises a ring of insulating material, made integrally by moulding to a diameter substantially greater than that of the first body portion, and each branch of the intermediate portion comprises a first portion which extends the first body portion, together with a second portion which is divergent radially up to the ring.

Abstract: For electric motor collectors with lamella inner cross members, which serve for anchoring the individual lamellas, protrude inwards running at least predominantly parallel to the collector axis and are provided with undercut surfaces, which are to be grasped from behind by reinforcing rings. Reinforcing rings are proposed which, aside from a metallic clamping ring, comprise a supporting ring, which is fitted positively into the metallic clamping ring and forms a double body with the clamping ring and is formed from a material, which is resistant to compression and insulating even at high operating temperatures. With this, reinforcing rings are produced from two partial rings, which are easily manufactured and easy to press together, or by the supporting ring which is brought into the clamping ring by injection molding. The reinforcing rings form a unit which can withstand extremely high thermal and mechanical stresses and imparts the collector with very high stability under load and fatigue endurance.

Abstract: A brush holder body for a dynamoelectric machine comprising a molded body, integrated cantilever fingers molded into the body, the cantilever fingers extending radially inward from distal portions of the body, the cantilever fingers having a normal position into which they are molded extending at an angle to a plane of a commutator clearance opening the angle having a direction extending away from a motor armature position, wherein the cantilever finger is flexible and upon receipt of a force, flex in the direction of the armature, wherein the brush holder also comprises a snap feature for retaining the cantilever finger in a second position in which the cantilever finger prevents movement of a brush into the commutator clearance opening, wherein in the normal position, the cantilever finger allows movement of the brush into the commutator clearance opening and the cantilever finger does not contact a commutator of the dynamoelectric machine.

Abstract: An improved commutator anchoring system and methods of manufacturing such a system are disclosed. The system includes a wound fiberglass or other ring embedded in the internal core of the commutator to reinforce the resulting structure and enhance its thermal and mechanical stability. The reinforcing ring also functions as a form about which various anchors can be patterned, increasing their uniformity over free-form designs.

Abstract: A slip ring unit arranged to be force-fitted on to an alternator shaft, especially a motor vehicle alternator shaft, is made by moulding insulating material over electrically conductive elements so as to encapsulate the latter. It has a generally cylindrical body which includes two slip rings at its outer surface, the slip rings being connected to two electrical connecting elements for connecting the slip ring unit to the ends of winding wires of the alternator. The body of the unit has a bore for accommodating the alternator shaft. The insulating material is extended beyond one of the two slip rings, to define a collar at that end of the unit on which the fitting force is to be applied. At least one notch is formed in the extension constituted by the collar, these notches extending through the whole axial thickness of the latter so as to leave one side of the adjacent slip ring exposed. The applied fitting force can then be exerted directly on the slip ring, through the notch.

Abstract: A miniature motor in which stators are mounted in an interior of a casing, and a preassembled commutator is provided on a rotor rotatably disposed to face the stators. The commutator has a sleeve body having a cylindrical portion provided with a flanged portion and a plurality of recesses, directed outwardly, in a side wall of the flanged portion, with the sleeve body being made of insulating material and mounted on a rotary shaft of the rotor. The commutator also has a plurality of conductive commutator pieces each having a body portion formed in an arcuate shape and mounted on an outer circumferential surface of the cylindrical portion, a terminal portion and at least one retainer portion, with each of the terminal portion and the retainer portion being received in the recesses.

Abstract: Carbon commutator segments are secured to a base member by means of integral anchor pieces disposed within axially extending, cruciform-section slots formed in the outer cylindrical surface of an insulating base member. Elongate contact members having lateral edges seated in lateral parts of the slots are embedded in the anchor pieces and are each provided, at one end, with a terminal for connection to an armature winding lead wire. The carbon segments and the integral anchor pieces are formed by enclosing the base member, together with assembled contact members, in a mold and then injecting a moldable mixture of carbon powder and carrier material into the space between the mold and the assembly with the moldable mixture filling the slots and embedding that portion of each contact member disposed within the slots. When the injection molded layer has solidified, an annular-section outer portion of this injection molded layer is divided into segments by means of axially-extending radial cuts.

Abstract: A drum commutator for electrical machines has an isolating material drum and a plurality of commutator plates composed of an electrically conductive material, the commutator plates being mounted on a periphery of the isolating material drum near one another and electrically separated from one another by axial slots, each of the commutator plates being provided with a surface coating composed of carbon material and with a connecting lug for an armature winding of an electrical machine, each of the commutator plates having at least one depression at its lower side placed on the isolating material drum and being also provided with a radial passage which opens in the depression and has a reduced size relative to the depression, the carbon material of the surface coating filling the passage and the depression as a one-piece structure.

Abstract: A planar carbon segment commutator has contact members, with terminals, attached to the front surface of an insulating base member by means of overmoulded carbon segments formed integral with anchor pieces disposed within apertures in the base member. Each aperture has a second part disposed rearwardly of a first part having a smaller cross-section than the second part and the anchor piece disposed within the aperture has a locking portion which fills the second part of the aperture to thereby resist withdrawal of the anchor piece from the aperture. The contact members are embedded in the carbon segments and have holes filled with carbon segment material to increase interlocking between the contact members and the segments.

Abstract: Carbon commutator segments are secured to a base member by means of integral anchor pieces disposed within axially extending, cruciform-section slots formed in the outer cylindrical surface of an insulating base member. Elongate contact members having lateral edges seated in lateral parts of the slots are embedded in the anchor pieces and are each provided, at one end, with a terminal for connection to an armature winding lead wire. The carbon segments and the integral anchor pieces are formed by enclosing the base member, together with assembled contact members, in a mould and then injecting a mouldable mixture of carbon powder and carrier material into space between the mould and the assembly. When the injection moulded layer has solidified, an annular-section outer portion of this injection moulded layer is divided into segments by means of axially-extending radial cuts.

Abstract: A method for producing a molded plastic and copper flat rotary switch or commutator with parts of the segments lying in a cylindrical surface is disclosed. A cup-shaped unfinished piece is formed by modification of a flat material, having an outside annular flange and a number of axial grooves which are radially open on the inside as well as distributed uniformly around the periphery corresponding to the number of segments in the cylindrical part of the unfinished piece, on the outside of the cylindrical wall of the unfinished piece, a layer with a thickness which corresponds to the radial thickness of the material parts occluding the grooves radially on the outside is pushed, beginning at the flat part corresponding to the subsequent brush contact surface, toward the free end of the casing with formation of the annular flange and opening of the grooves.

Abstract: A molded rotor assembly (20) for a vehicle alternator and method for making the same are disclosed. The rotor assembly includes first and second pole pieces (24,26) aligned along a longitudinal axis (40), the pair of pole pieces (24,26) defining a region therebetween. A coil wire (46) is located in the region. The pole pieces (24,26) and a slip ring assembly (36) are mounted on a rotor shaft (38). The slip ring assembly (36) has a pair of slip rings (102,104) connected to a pair of terminals (96,98) which are attached to respective free ends of the coil wire (46) to form a pair of connections (126,128). A molded insert (22) is injection molded filling the region between the pole pieces (24,26) thereby encapsulating the connections (126,128) and the coil wire (96) and forming a smooth cylindrical periphery on the rotor assembly (20).

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: A commutator has such a construction that a flange having an outside diameter larger than the outside diameter of a cylindrical body is provided integrally with the cylindrical body in the vicinity of one end of the cylindrical body; guide grooves formed in a circular arc shape in cross section are provided on the flange at the boundary of the flange to the cylindrical body; engaging pieces passing through the guide grooves are provided on one end of a commutator segment; and engaging pieces are caused to deform plastically to fixedly fit the engaging pieces to the flange.

Abstract: A plate-like material is rounded in the form of a cylinder so as to form a main body of a commutator to which an end of a winding for an armature coil of an electric motor is electrically connected, and both ends of the plate-like material are opposed to each other so as to define a joint portion therebetween. When a molten soldering material is introduced into the joint portion and solidified therein, the joint point is closed by the soldering material, thereby making it possible to mold the main body of the commutator, which is shaped substantially in the form of a jointless cylinder. The commutator can be easily fabricated and the manufacturing cost thereof can also be reduced as compared with a case where the main body of the commutator is fabricated from a pipe-shaped material. Since the joint portion can reliably be closed, resin used to charge the inside of the main body of the commutator therewith at a subsequent step can be prevented from extruding toward the outside of the main body.

Abstract: A commutator has a central support supporting a plurality of conductive segments separated by a plurality of insulative segments. In addition to providing an insulative function between the conductive segments, the dielectric constant, the area, and the thickness of the insulative segments are chosen so that they provide a capacitive effect, which capacitive effect suppresses current peaks during operation of the commutator. Preferably, the dielectric constant is greater than 10. The central support may include a metal shaft and an insulating ring, which insulating ring is preferably of material with a lower dielectric constant thereby to suppress-shorting between the shaft and the conductive segments. It is particularly advantageous if the conductive and insulative segments are of ceramics material since this provides good wear resistance. In further alternatives, capacitors are formed between the conductive segments by rings or other bodies of insulative materials of a suitably high dielectric constant.

Abstract: In an armature wherein a plurality of base metals 15 electrically insulated from one another are solidly secured to the surface of a boss portion 10, carbon protective members 18 are jointed to the surfaces of the base metals 15, respectively, through a solder layer 19 and coil ends 5 of an armature core are jointed to the risers, an auxiliary electrode portion 17 is formed integrally with the riser 12 on each of the base metals 15.

Abstract: A slip ring device comprises a cylindrical body of an insulating material, at least one ring of an electrically conductive material fitted on the outer periphery of the cylindrical body, at least one strip member of an electrically conductive material arranged on the outer periphery of the ring, a coupling member, situated between the strip member and the outer periphery of the ring, for electrically coupling the strip member and the outer periphery of the ring, at least one lead member of an electrically conductive material, having one end portion electrically connected to the ring and the other end portion led out of the inner periphery of the cylindrical body, and a brush unit of an electrically conductive material, situated in electrical contact with the strip member.

Abstract: A slip ring with which a pair of brushes make contact includes a conducting portion which extends along an outer periphery of the slip ring over an angle of preferably about 210 degrees, and a non-conducting portion which extends over an angle of about preferably 150 degrees. A conductor which forms the conducting portion has a ring-like shape and also forms the non-conducting portion. The portion of the conductor which corresponds to the non-conducting portion has a small radius such that it is buried in an insulating resin material, a window through which an insulating resin material is exposed, or a recess through which an insulating resin material is exposed. The ring-like conductor provides a balanced center of gravity to the slip ring. The conductor may also include two or more conducting portions and two or more non-conducting portions.

Abstract: Four side walls surrounding a recess in the center of a commutator segment are extended to overhang toward the recess comprising claws and cut-and-raised protrusions, thereby ensuring that the commutator segment is securely engaged with the resin filled in the recess against any of the triaxial stresses due to centrifugal force, rotating force, and tensile force. The volume of cutting in the insulating resin at undercut portions is reduced. The internal and cut-and-raised protrusions are molded by cylindrically bending oriented progressive dies made of plate material.

Abstract: A flat commutator is described with carbon segments, metal segment-supporting parts supporting these and a hub body of an electrically insulating moldable plastic compound, which supports the segment-supporting parts, a solder layer is provided lying between the two segments for the connection between the carbon segments and the segment-supporting parts. The side surfaces of directly adjacent carbon segment-supporting parts which are facing one another are covered completely by the moldable plastic compound of the hub body. The method for producing this commutator is also described wherein the segment-supporting parts are soldered together with an annular plate later forming the carbon segments before the hub body is fitted onto the segment-supporting parts. The intermediate spaces between the segment-supporting parts are filled with moldable plastic material. Not until after the fitting is the annular plate subdivided into the individual carbon segments.

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 and 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: A collector for an electric motor or generator with lamellae, which are distributed symmetrically to a collector axis at the periphery or at a front face and which are embedded in a basic body of insulating material, the collector having a central opening, which is designed with respect to its diameter for a press fit on the shaft of the electric motor or generator and is reinforced by a bushing element of higher strength for absorbing the seating and pressing-on forces, is designed in the sense of being easier and less expensive to manufacture, being handled more readily and less critically while being pressed onto the shaft of a motor and being more robust and having a longer service life, so that the busing element has an internal diameter, which is larger than the diameter of the opening, and that the bushing element is covered on the inside by a layer of insulating material.

Abstract: A slip ring with which a pair of brushes make contact includes a conducting portion which extends along an outer periphery of the slip ring over an angle of preferably about 210 degrees, and a non-conducting portion which extends over an angle of about preferably 150 degrees. A conductor which forms the conducting portion has a ring-like shape and also forms the non-conducting portion. The portion of the conductor which corresponds to the non-conducting portion has a small radius such that it is buried in an insulating resin material, a window through which an insulating resin material is exposed, or a recess through which an insulating resin material is exposed. The ring-like conductor provides a balanced center of gravity to the slip ring. The conductor may also include two or more conducting portions and two or more non-conducting portions.

Abstract: Lower coils (5b) and upper coils (5a) are inserted to slots (12) of a cylindrical armature core (4). The upper coils are used as crossover lines (102a) at the side of commutator (10) and form commutator segments. The crossover lines are approximately deviated by a pole pitch (yf) at the commutator and inserted to other slots as lower coils. The lower coils are used again as crossover lines and deviated approximately by the pole pitch at the opposite side of the commutator so as to be inserted again to the slots as the lower coils. An insulating resin (11) are forced to push into inner peripheral sides of the armature core, and the crossover lines forming a squirrel cage type shape and extending cylindrically from the core.

Abstract: A commutator includes a plurality of commutator segments disposed in circular configuration and equally spaced from each other in a circumferential direction. Each commutator segment has a contact portion for contact with a brush and an anchoring portion which forms a recess in cooperation with the contact portion. A ball made of insulation material is disposed between each two adjacent commutator segments in such a manner that ball is partly engaged with both recesses of adjacent commutator segments. A cylindrical hub made of synthetic resin is molded with the anchoring portions of the commutator segments and the balls.

Abstract: An assembled commutator has a thermoplastics base supporting segments. A ring 15 of high temperature, non-softening material, such as phenolic, fits on a shelf on the base beneath tangs which are for hot connection, particularly forging, to an armature wire. The ring is held in place by fingers on the tangs.

Abstract: An improved commutator for an electric motor and a method of making the same wherein the outer surface of a commutator sleeve molded of a synthetic resin is coated with an insulating coating layer of an electrically insulating coating material. The molded commutator sleeve thus coated is protected from oxidative degradation and cracking which would otherwise result in removal of a commutator bar and insulation failure.

Abstract: The armature has windings supported by a core mounted on a shaft. The windings and the wires connecting the windings to a commutator are encapsulated in an insert-molded body of plastic, typically nylon. A ring having radially inwardly extending arms (33) equal in number to the number of commutator slots is mounted on the commutator. The arms are lcoated in respective slots between the commutator segments and are stiff enough to block flow of plastic material along the slots during insert molding of the body of plastic.

Abstract: An armature for a motor comprises a winding and a commutator. Each commutator segment has a brush contacting portion and an integral terminal portion connected to a connector portion of the winding. A commutator base includes housings which receive the terminal portions and which have slots for positioning the connector portions of the winding relative to each housing. Each terminal portion has a slot which straddles and grips the connector portion positioned relative to a respective housing. At least one and preferably all terminal portions have two slots arranged side-by-side so that the two side-by-side slots of one of the terminal portions can straddle and grip the lead end and tail end of the winding, respectively.

Abstract: A D.C. motor comprising an armature core, an armature coil, a commutator and an armature shaft is disclosed. The armature shaft is provided with a whirl-stop portion having a length sufficient to allow the armature core and the commutator to be fixed to it. The whirl-stop portion may be formed by rolling or knurling.

Abstract: Anchoring elements of commutator lamellas are formed in a manner that of the inner circumference of the commutator mantle, longitudinal ribs 2 each having two longitudinal ridges 2a are formed by deforming without cutting the material of starting outline A, such as by trenching by plowing, the material mainly moving in a radial direction, whereby between the ribs 2 the longitudinal interspaces 3 are sharply defined. Subsequently, the ridges 2a are flattened by a flattening mandrel, whereby the prevailing part of the ridge mass is deformed in a tangential direction into the area of the longitudinal interspaces 3.

Abstract: A commutator 4 for a starter motor comprises a plurality of segments 4a electrically connected to armature coils 3, an insert member 4b fitted to an armature shaft 2, and a glass-fiber-reinforced phenol resin 4c molded to integrate the segments with the insert member, wherein mica particles in a range of 5%-10% by weight are uniformly contained in the resin.

Abstract: A method of manufacturing an armature of an electric rotary machine comprising the step of: fixedly attaching an armature core to a shaft which is a constituent component of the armature; winding armature coils in slots formed in the outer circumference of the armature core, the lower and upper lead-out portions of the armature coils being axially extended to a commutator arrangement space where a commutator is to be arranged; welding the respective end portions of each pair of the upper and lower lead-out end portions so as to join the upper and lower lead-out end portions in each pair with each other under the condition that the upper and lower lead-out end portions in each pair are arranged vertically one on the other and parallelly to each other while securing concave portions at the welding-joined portions to thereby form each of commutator segment portions; arranging the commutator segment portions in alignment at predetermined intervals circumferentially around the shaft; and molding and fixedly attach

Abstract: An improved commutator usable for an electric motor of the type adapted to be press fitted onto the support shaft of a rotor which is accommodated in the motor. The inner wall of the commutator comprises a plurality of larger diameter portions of which inner diameter is larger than the outer diameter of the support shaft and a plurality of press fitting portions of which inner diameter is smaller than the outer diameter of the support shaft. Press fitting of the commutator onto the support shaft is achieved by elastic bending deformation of the press fitting portions on the inner wall of the commutator in the outward direction. Typically, the inner wall of the commutator comprises three larger diameter portions and three press fitting portions. No preliminary machining is required on the inner wall of the commutator before press fitting is effected. The amount of press fitting allowance can be increased remarkably compared with any conventional commutator.

Abstract: A commutator for use with a DC motor or a DC generator. The parent metal of the segments of the commutator is formed with bulging portions which have their outer surfaces generally coextending with the outer surfaces of protecting portions for contacting brushes. This commutator is manufactured by forming a cylinder of a plate of a conductive material, by forming a plurality of pawls on the circumference of the cylinder, by molding a boss of a synthetic resin in the cylinder, by forming a plurality of notches in one end of the cylinder, and by cutting the trunk of the cylinder with a plurality of slits to form a plurality of separate segments.

Abstract: A molded commutator is made up of segments arranged in a ring with their brush contact surfaces facing inwardly and forming a cylindrical shape. A matrix of plastic is molded between and around the outside of the segment ring in order to separate the segments electrically and to hold them in the ring configuration. A reinforcing metal casing serves to contain the commutator against breaking up due to centrifugal forces experienced during rotation. An alternate embodiment uses metal bands embedded within the matrix for this purpose.

Abstract: A slip ring assembly for an alternator or like electrical apparatus is disclosed which has been particularly configured for highly efficient formation by an injection molding process. The assembly includes a unitary body configured for mounting on the rotor shaft of the associated apparatus, with the assembly further including first and second axially spaced slip ring members positioned on the body. First and second terminals are provided which are respectively electrically joined to the first and second slip ring members, with the terminals extending axially of the body and outwardly of an end of the body which is adjacent to the first slip ring member. The configuration of the body of the assembly is such that it can be very efficiently injection molded, with the slip ring members and terminal elements thereafter positioned on the body for completing fabrication of the assembly.

Abstract: A commutator assembly is disclosed and includes a core of insulating material surrounded by a plurality of commutator segments. A disk-like riser plate is molded at one end of the commutator with slots for receiving and holding the coil ends of an appropriate motor armature in engagement with respective ones of the commutator segments. Outwardly flared walls are molded on the side of the riser plate facing the armature, the walls diverging toward the slots for guiding the coil ends into the slots.

Abstract: To permit use of asbestos-free insulating material in the manufacture of commutators, while insuring reliable retention of the commutator segments, the commutator segments are formed with projecting leg portions which are embedded in the insulating body, a first leg portion being formed with a projection which extends circumferentially towards the second leg portion of a neighboring segment and overlaps, at least in part, the neighboring segments and forms therewith an interlocking fit, interlocking at least in radial direction, the interlocking fit leaving a gap between the first leg portion of one segment and the neighboring segment to provide for insulation between the segments.

Abstract: A commutator includes a hub, a segment set having armoring and an inner cover surface, and insulation arranged between the hub and the segment set. The segment set is forcefittingly coupled with the hub by support forces directed toward its inner cover surface. The result of this arrangement is that the hub and the insulation are radially prestressed by tension forces caused by the armoring of the segment set.

Abstract: A slip ring assembly comprises an insulating body having a pair of slip rings on its external surface, each slip ring having electrically connected thereto a respective connector element a part of which is disposed radially inwardly of the slip rings. The body has an internal bore which receives a shaft of a rotary electric machine in use, a side wall of the bore being provided with axially extending recesses which are disposed radially inwardly of the connector element parts respectively. The presence of these recesses, which may alternatively be of helical or annular configuration, ensures that the connector elements do not contact the aforementioned shaft in operation and thereby create a short-circuit. The slip ring assembly is produced by placing the rings and the connector elements in an annular mould cavity whose radially inner surface has projections thereon which correspond to the desired configuration of the recesses in the completed assembly.

Abstract: Anchoring elements of commutator lamellas are formed in a manner that of the inner circumference of the commutator mantle, longitudinal ribs 2 each having two longitudinal ridges 2a are formed by deforming without cutting, the material of starting outline A, such as by trenching by plowing, the material mainly moving in radial direction, whereby between the ribs 2 the longitudinal interspaces 3 are sharply defined. Subsequently, the ridges 2a are flattened by a flattening mandrel, whereby the prevailing part of the ridge mass is deformed in tangential direction into the area of the longitudinal interspaces 3.

Abstract: A molded commutator is made up of segments arranged in a ring with their brush contact surfaces facing inwardly and forming a cylindrical shape. A matrix of plastic is molded between and around the outside of the segment ring in order to separate the segments electrically and to hold them in the ring configuration. A reinforcing metal casing serves to contain the commutator against breaking up due to centrifugal forces experienced during rotation. An alternate embodiment uses metal bands embedded within the matrix for this purpose.

Abstract: The external segments of a commutator for rotating electrical machinery are mechanically interlocked to a molded matrix by a plurality of tang assemblies having protrusions at their ends for engagement deep within the internal matrix, to hold the segments against centrifugal forces. The tang assemblies also have anchoring bars shaped for interlocking engagement with the longitudinal channels located on the inner surfaces of the segments.

Abstract: Commutator for a flat motor which includes fan-shaped brush contact pieces and connection pieces upraised from said brush contact pieces and kept electrically integral therewith wherein a plurality of segments made of superior conductive material are arranged in an annular form in a specified spaced apart relation in such a way as said connection pieces are positioned at an inner edge, said segments are insulated with each other by an insulator material, top ends of said connection pieces are bent to an inverted-U shape, their leading ends are buried in said insulator material, connection wires of an armature winding are pushed into the slits made at the top ends of said connection pieces so as to connect the segments with the armature winding.