Abstract: A split sprocket for use in a modular conveyor belt is disclosed. The split sprocket includes first and second portions that may be selectively arranged in a first configuration in which the sprocket maintains a fixed axial position on the shaft and a second configuration in which the sprocket can axially float along the shaft.

Abstract: A transmission wheel assembled of at least two segments (1) on a shaft (12), the inner arc surface (3) of which and the shaft (12) have essentially the same radius (R), and which segments' (1) outer surfaces (9) have profiled surfaces that transmit the power of the transmission wheel. Between the segments' (1) welded-together end faces (4) there are gaps on those sections of the end faces (4) that are not welded, which creates a press fit between the shaft (12) and the inner arc surface (3) of the transmission wheel. The weld connecting the transmission wheel segments' (1) end faces (4) may be incomplete, meaning that it does not reach the shaft (12).

Abstract: A track drive for outdoor power equipment has a support frame with a centerline and a hub bearing attached to the support frame. A drive sprocket having a nesting interior half and exterior half is attached to the hub bearing, which enables the drive sprocket to rotate relative to the support frame. The drive sprocket is attached to an associated drive hub of a piece of outdoor power equipment. Drive sprocket teeth are spaced radially about the drive sprocket, with a first set of drive teeth attached to the interior half sprocket and located on an interior side of the support frame. A second set of drive teeth are attached to the exterior half sprocket and located on an exterior side of the support frame. The drive sprocket transmits a rotational force to an endless track to rotate the endless track and propel the outdoor power equipment.

Abstract: A two part sprocket wheel engages modular belt modules in a conveyor belt. The sprocket wheel's periphery elements' outer edges form a full circle. On each inner periphery four engagement ridges are provided. When the sprocket wheel is mounted around the axle, only the engagement ridges touch and engage the axle. The sprocket wheel construction between the engagement ridges is removed from the drive axle. It is possible to flush and clean the areas around the drive axle being partly covered by the sprocket wheel in an easy and accessible manner. The engagement ridges have a very limited engagement area in order to contact the drive axle and thereby convey the torque forces from the drive axle to the teeth of the sprocket wheel. The engagement ridges are in very firm engagement with the drive axles, such that no material may remain where the engagement ridges engage the drive axles.

Abstract: A cinch direct mount 2X ring system is disclosed. One embodiment discloses a chainring assembly having a drive side crank arm with a chainring assembly interface including a plurality of splines, a circumference, and an axial length. The chainring assembly includes a first chainring having a first outer diameter and a first center assembly shape. The chainring assembly includes a second chainring having a second outer diameter and a second center assembly shape, the second outer diameter being different than the first outer diameter. The chainring assembly also includes a fastener to couple the first chainring and the second chainring with the chainring assembly interface, such that at least one of the first center assembly shape or the second center assembly shape engages with the plurality of splines.

Abstract: The invention relates to a people conveyor drive (40) of a people conveyor (1) comprising a plurality of treads (13) interconnected to form an endless tread band (12). The people conveyor drive (40) comprises a tension member drive system (25) configured for driving the endless tread band (12), and a shaft (50) having a shaft main portion (52) and at least one shaft support portion (54). The at least one shaft support portion (54) is supported by at least one shaft bearing (57) to be rotatable around a shaft axis (A). The shaft (50) is configured for engaging with an endless tread drive tension member (15). The shaft (50) has a split shaft configuration in which the shaft main portion (52) is detachably coupled to the at least one shaft support portion (54).

Abstract: A shaft and sprocket assembly having an elongate shaft, a sprocket wheel and at least one bracket member. The sprocket wheel encircles and engages the shaft wherein torque is transferrable between the shaft and the sprocket wheel. The sprocket wheel includes radially outwardly extending teeth and is formed by a plurality of sprocket members. Each of the sprocket members defines an angular portion of the sprocket wheel less than 360 degrees. The bracket member detachably secures the individual plurality of sprocket members together thereby allowing the sprocket members to be easily removed from and installed on the shaft. The bracket member is positioned such that no torque is directly transferred from the shaft to the bracket member. The shaft and sprocket assembly can be used in a variety of applications including in the feederhouse of an agricultural combine.

Abstract: A rotatable annular bicycle component comprises an outer annular member, an intermediate supporting member, and a hub engaging member. The outer annular member comprises a first material. The outer annular member is attached to the intermediate supporting member. The intermediate supporting member comprises a second material different from the first material. The hub engaging member is configured to be attached to the intermediate supporting member and is configured to engage with a bicycle hub assembly. The hub engaging member comprises a third material different from the second material.

Abstract: A sprocket wheel built up from at least two synthetic wheel parts (2, 3), comprising a hub part (4a, 4b), a gear ring (5) and a body part (6) connecting the hub part and gear ring, having a central plane forming a plane of symmetry of the body part, at least one fastener housing (7) divided over the two wheel parts, having a fastener hole (8) extending along a centerline situated in the central plane, for receiving a fastener (9), and, at least one gear ring opening (10) extending through the gear ring, situated in line with the fastener hole, characterized in that the body part comprises a recess (11) accessible from a side of the body part to a fastener, which recess is situated in line between the gear ring opening and the fastener housing and whose passage towards the fastener housing is greater than the passage of the gear ring opening (10).

Abstract: A ring cam for a fluid-working machine is formed from a plurality of segments. The segments comprise a leading cooperating formation which has a piston facing surface which forms part of the working surface, at a trailing end, and which is recessed from the working surface at a leading end, and a trailing cooperating formation which has a piston facing surface which forms part of the working surface at a leading end, and which is recessed from the working surface at a trailing end. The segments having piston facing surfaces which are in compressive stress such as to partially or fully compensate for tensile stress arising from the action of rollers in use. The segments form a wavelike cam surface and attachment means are provided, through the working surface, on whichever of the leading or trailing surfaces thereof is subject to lowest forces from pistons in use.

Abstract: A split sprocket for belts or chains. The split sprocket comprises two sections that slide together along parallel slide tracks that are perpendicular to two opposite walls of the sprocket's bore. The slide track includes male T-shaped, V-shaped, or jigsaw-puzzle-shaped beams on one of the sections that slide into mating female slots in the other section. The mated slide tracks prevent the sections from separating in all directions except the separation direction along the slide tracks. A fastener through one of the sections into the other prevents the assembled sprocket sections from sliding apart along the slide tracks.

Abstract: A conveyor sprocket assembly generally includes a support shaft, at least one conveyor sprocket slidably engaging the support shaft, and an abutment stop positioned adjacent the conveyor sprocket. The abutment stop is configured to be removed to allow the conveyor sprocket to slide axially along the support shaft.

Abstract: A repair roller may include a cylinder with components that may have an outer surface, an inner surface and end surfaces. Each of the end surfaces may include a mating portion and outer portions that extend from the ends of the mating portion. A pair of complementary interlocking elements may be disposed within the mating portion for secure engagement of the components.

Abstract: A riser formed from a plurality of curved cylindrical segments with vertical side edges having mating vertically tapered projections and slots brought into interlocking engagement to pull confronting surfaces together as the tapered elements become increasingly mechanically engaged. The segments are assembled by a sliding engagement of the protruding mating element of one segment into the vertically tapered slot of an adjacent segment. When sufficient segments are joined together horizontally to complete a ring except for a last adjacent pair of vertical side edges, the ring is warped to align the protruding mating element of the last adjacent pair of vertical side edges with an opposite end of the adjacent tapered slot. Thus aligned, the final protruding mating element and tapered slot are then slipped together while un-warping the joined segments forming the remainder of the ring until the top and bottom ends of all the segments are aligned.

Abstract: A clutching mechanism (20) for a cultivating tiller. The tiller has an engine (16) mounted on a frame (12) with a rotatable output shaft (40), a rotatable working shaft (22), and a transmission (18) operatively connecting to the working shaft, the transmission having a rotatable transmission shaft (42) coaxially aligned with the output shaft of the engine. The clutching mechanism includes an upper half pulley (52) attached to the output shaft, and a lower half pulley (54) attached to the transmission shaft, wherein the upper half pulley and lower half pulley are coaxially positioned in a facing but non-contacting relationship such that the upper half pulley is able to freely rotate with respect to the lower half pulley. The clutching mechanism also includes a belt (62) positioned between the upper half pulley and the lower half pulley, and a tensioning assembly (70) configured to selectively tension the belt so that the belt transmits rotation of the upper half pulley to the lower half pulley.

Abstract: A coupling device (10) for a gear wheel (12), a pulley or other similar units comprising a support (18) for a gear wheel (16) or an operating portion of the pulley or unit, means for centering and drawing the crown gear (16) or the operating portion on the support and means for holding the crown gear (16) or operating portion against the support (18) along a parallel direction relative to a rotation axis of the gear wheel or pulley or unit, said means comprising a locking member (34) suitable to be fixed to the support (18) for defining an abutment for the crown gear (16) or operating portion.

Abstract: A sprocket wheel built up from at least two synthetic wheel parts (2, 3), comprising a hub part (4a, 4b), a gear ring (5) and a body part (6) connecting the hub part and gear ring, having a central plane forming a plane of symmetry of the body part, at least one fastener housing (7) divided over the two wheel parts, having a fastener hole (8) extending along a centerline situated in the central plane, for receiving a fastener (9), and, at least one gear ring opening (10) extending through the gear ring, situated in line with the fastener hole, characterized in that the body part comprises a recess (11) accessible from a side of the body part to a fastener, which recess is situated in line between the gear ring opening and the fastener housing and whose passage towards the fastener housing is greater than the passage of the gear ring opening (10).

Abstract: A chain wheel arrangement for driving or reversing stations of underground scraper chain conveyors, comprising a chain wheel (1), a chain-wheel shaft (3) comprising a splined portion (11) between two offset-diameter shaft stub portions and to which the chain wheel (1) can be fastened in rotational engagement by axial sliding on to it, also comprising bearing shells (5) receiving bearings for the chain-wheel shaft (3), disposed on each side of the chain wheel (1) and adapted to be fastened in bearing-shell recesses, open at the edges, in the side cheeks of the driving or reversing station, also comprising bearing support rings (26) which abut the outer cage (4B) of the bearings (4), and securing means comprising spacer sleeves (16) for axially securing the chain wheel (1) relative to the splined portion (11), in which the spacer sleeves (16) rest loosely between the bearings (4A) and the chain wheel (1), wherein a clamping cover (30) is fastened to at least one shaft end (13) and presses against a clamping sle

Abstract: A drive system monitors the rotary motion of a shaft and transmits the rotary motion to an encoder. The drive system includes a drive sprocket that is coupled to the rotating shaft by a pair of disc-shaped hubs with the sprocket being sandwiched between the two hubs. The sprocket has an axial bore formed therethrough and is split into semi-circular halves to facilitate circumferential mounting of the sprocket on the shaft to be monitored. The two disc-shaped hubs which couple the sprocket to the shaft have axial bores formed therethrough and are split into two segments each of which is preferably less than semi-circular to allow the hubs to be clamped in circumferential engagement on shafts of various diameters within a predetermined range of diameters. A chain is connected to the drive sprocket for transmitting the monitored rotary motion of the shaft to the driven sprocket of the encoder.

Abstract: A split sprocket assembly, related apparatus, and a method of mounting a sprocket to a rotatable structure, such as a drive or idler drum, are disclosed. In one embodiment, the sprocket assembly is comprised of at least three sections or segments, each of which is secured to the adjacent section or segment by a fastener, such as a tangentially-extending bolt and nut combination. The sprocket assembly includes a plurality of receivers, each for receiving a key that corresponds to a keyway formed in the rotatable structure. In one embodiment, at least one of the keyways is truncated and, thus, extends only partially across the rotatable structure in the axial direction. A key substantially identical to the truncated keyway in length and width is placed therein, such that the sprocket is prevented from traveling or “walking” along the rotatable structure.

Abstract: This invention relates to endless tracks and systems used to propel tracked vehicles [i.e., vehicles which use endless tracks rather than tires to contact the terrain over which they are driven, e.g., tractors, tanks, bulldozers, etc.] and, more particularly, to an improved split wheel design and installation process therefore. The track is made from a polymer adapted to travel over a drive sprocket, a plurality of guide wheels and a tension wheel. A new step by step methodology allows the endless track to be installed and used more efficiently when the tension wheel or the drive sprocket is replaced by a split wheel.

Abstract: The invention relates to a driving sprocket for a bicycle crankset having a toothed ring whose ring is divided into a plurality of segments (14a, 14b, 14c, 14d), the segments being borne by a frame (16) that is rotationally movable about a crankset axle, each sprocket segment being movable between a low position and a high position, a system for transferring each segment to transfer said segment from one position to another, and an indexing mechanism to control the system for shifting the segments. The sprocket is characterized in that each segment (14a, 14b, 14c, 14d) is floatingly mounted with respect to the frame (16) and in that it is guided in its transfer movement along a trajectory having a radial component and a tangent component.

Abstract: A sprocket ring has outwardly protruding spaced teeth to engage the motorcycle drive chain and an inner circular flange to interconnect with the sprocket hub. The sprocket hub has an outer circular flange to interconnect with the sprocket ring. Mating holes in the flanges receive bolts therethrough to interconnect the ring and the hub.

Abstract: A split sprocket assembly, related apparatus, and a method of mounting a sprocket to a rotatable structure, such as a drive or idler drum, are disclosed. In one embodiment, the sprocket assembly is comprised of at least three sections or segments, each of which is secured to the adjacent section or segment by a fastener, such as a tangentially-extending bolt and nut combination. The sprocket assembly includes a plurality of receivers, each for receiving a key that corresponds to a keyway formed in the rotatable structure. In one embodiment, at least one of the keyways is truncated and, thus, extends only partially across the rotatable structure in the axial direction. A key substantially identical to the truncated keyway in length and width is placed therein, such that the sprocket is prevented from traveling or “walking” along the rotatable structure.

Abstract: An adaptor for power transmission in a pulley and shaft. Two adaptor portions are disposed on opposite sides of the pulley and drawn axially together to capture the pulley therebetween. At least one of the adaptor portions is attached to a quick disconnect bushing on the shaft. A connecting member is tightened to draw the adaptor portions and the bushing together. Preferably, the bushing is tapered and the adaptor portions are correspondingly tapered, providing a radially directed force. The adaptor portions are particularly suited for use with a pulley that is substantially formed of plastic.

Abstract: A guide sprocket assembly for use in combination with a non-driven, rotating tail shaft. The guide sprocket assembly includes a lock plate assembly securely fixed to the tail shaft for rotation along with the tail shaft. The lock plate assembly includes an annular sprocket groove that receives an annular guide sprocket having a plurality of projecting teeth spaced along its outer circumference. The guide sprocket is retained within the annular sprocket groove by a sprocket retainer. The combination of the guide sprocket and sprocket retainer are freely rotatable within the annular sprocket groove relative to the lock plate assembly. The teeth of the guide sprocket engage a drive chain, and the guide sprocket can rotate either in the direction of rotation of the tail shaft or in an opposite direction to properly align the individual links of the drive chain with the teeth formed on the guide sprocket.

Abstract: A sprocket of the type typically used for driving a plastic conveyor belt is split through the drive shaft hole at its center, so that the sprocket can be assembled over a drive shaft without disrupting the conveyor assembly. Two sections which form the drive shaft preferably are identical, and may be machined from high molecular weight polyethylene. In a preferred embodiment the two sections are assembled together by interlocking features shaped as jigsaw puzzle pieces. The two sections are placed against the drive shaft and are moved together in the axial direction of the drive shaft, thus sliding the sections together. One or more fasteners may be provided at easily accessed locations to permit the two sections from sliding apart.

Abstract: A split sprocket assembly. The sprocket assembly does not require additional separate fasteners and extends substantially parallel to the axis of the drive shaft. Further, the sprocket assembly includes first and second sprocket sections having integrally formed connecting device to connect the sprocket members about the shaft. The connecting device preferably includes a projection formed on one sprocket section and a complementary recess formed on the other sprocket section. The geometry of the projection and the recess is preferably that of a dove-tail shape. The connecting device further includes a device for preventing axial movement of the sprocket sections relative to one another. In one embodiment, the sprocket assembly does not require any additional separate fasteners at all, and the preventing device includes locking members to provide a cylindrical snap fit.

Abstract: A split sprocket is formed in two opposing half sprocket parts of essentially identical conformation and structure. The halves, when married, form a typical sprocket which may also be a gear or drive pulley. A ring is adapted to engage a circular groove on each side of the sprocket so as to assure the two halves cannot part. A pair of screws also engages the two halves so as to firmly join them. One of the rings may have a cylindrical extension which when fitted into the sprocket adapts the sprocket for being mounted onto a smaller shaft. Each half of the sprocket may be fitted with a tongue and a tongue groove for aligning and maintaining alignment of the two halves.

Abstract: A chain drum arrangement for a central or double central scraper chain conveyor which includes a divided chain wheel and shell-type chain wheel segments which are attached and locked in rotation to or detachably from the shaft. The chain wheel is secured in its installed position on the shaft by ring parts disposed on both sides of the chain wheel, and at least one of these ring parts has a divided locking ring which can be taken off radially from the shaft in order to take off the divided chain wheel from the shaft.

Abstract: There is provided a sprocket for use in a wastewater treatment facility comprising a first portion, a second portion, and at least one fastener which snap locks the first portion to the second portion. There is also provided a sprocket for use in a wastewater treatment facility comprising at least one lightening hole, the sprocket being formed of non-metallic material.

Abstract: A pair of sprockets for use in a double chain and sprocket coupling for transmission of torque between shafts which are in approximate axial alignment with each other, and the abutting ends of which are closely spaced. Each of the sprockets is formed as one piece, and then cut into halves but for a web which is broken to separate the halve. The broken web serves to properly align and space the halves when placed over the end of a shaft to be coupled, and clamped thereon.

Abstract: The invention relates to a divisible sprocket wheel manufactured from synthetic material and having a gear ring (1b) and a hub portion (1a), comprising two wheel halves (1) which are manufactured by means of injection molding and have their axial faces (1f) abutting against each other, and means (3, 4) for enabling fixing the wheel halves together, wherein each wheel half (1) is solid and consists of a first synthetic material forming at least one half of the hub portion of the sprocket wheel; a second synthetic material forming at least one half of the gear ring of the sprocket wheel and the two radial outer faces (1d, 1e) of the wheel half, and a third synthetic material forming the internal portion (1e) of the body of the wheel half.

Abstract: A split sprocket assembly mountable on a shaft comprises a pair of substantially semi-circular sprocket halves, each of the sprocket halves having a mating face joined at a split line between the sprocket halves and having a concentric bore. Each of the sprocket halves further has a plurality of teeth provided about its periphery and a series of tooth pockets also formed about its periphery between each pair of adjacent teeth. A hub having a throughhole disposed around the shaft is disposed in the concentric bore. The sprocket halves and the hub include two sets of diametrically opposite, aligned apertures, each of the aligned apertures extending radially inwardly from one of the tooth pockets on the periphery of the sprocket halves and into the hub. A fastener is provided within each of the aligned apertures for joining the sprocket halves and the hub together to form a split sprocket assembly readily attachable and detachable from said shaft.

Abstract: Sprocket wheels for use in chain conveyors, for instance, are preferably of a divisible construction so as to enable each wheel to be removed from the shaft separately. Also, on the basis of considerations of hygiene, the outer side surface of such a wheel is preferably entirely flat when used in the food or beverage industry. Existing divisible wheels are either flat on the outside, but expensive, or not flat and cheap because they are made by injection molding. The synthetic sprocket wheel according to the invention is flat and cheap and comprises two wheel halves with axial planes abutting against each other, each wheel half consisting of two interconnected parts, made by injection molding, abutting against each other through a radial side face, with the cavities and ribs necessarily present for the injection molding process being located in the interior of the wheel half.

Abstract: Split sprocket wheels having interlocking tabs for forming a sprocket wheel assembly that is easy to install on and remove from a drive or idler shaft of a belt or chain conveyor. The invention provides thin, durable sprocket wheels split into at least two sectorial sections along seams extending from a central bore to an outer engagement surface. Mating tabs and receptacles at the edges of adjacent sectorial sections interlock the adjacent sections radially and circumferentially. Holes in the vicinity of the mating tabs and receptacles of adjacent interlocked sections admit locking means for holding the sectorial sections together in axial compression. The sprocket wheels can be ganged together at selected positions along a shaft with their bores in coaxial alignment by means of spacers interconnecting consecutive sprocket wheels along the shaft.

Abstract: A motorcycle drive pulley is diametrically split to eliminate the necessity for removing the motorcycle rear wheel in order to change drive pulleys. The split drive pulley bolts to the rear wheel of a belt driven motorcycle. The pulley has a first surface which faces away from the wheel and is generally convexly dished with respect to the wheel, while a second pulley surface faces and is adjacent to the wheel and is generally concavely dished with respect to the wheel. The pulley halves are diametrically symmetric, however the first and second surfaces are nonsymmetric. The pulley is constructed from a suitable self lubricating nylon or plastic which results in increased drive belt longevity. A method for installing the pulley without the need to remove the rear motorcycle wheel is also disclosed.

Abstract: A bushing and hub assembly are clamped together and clamped on a shaft by passing screws through an annular flange provided on the hub and into threaded openings in the bushing. The outside of the bushing is tapered and the inside bore of the hub has a taper which mates with the tapered outside of the bushing.

Abstract: A split sprocket with quick locking mechanisms is made of non-metallic components. The split sprocket is coupled to a shaft element by removable wedge members disposed between the sprocket's half members. Key members, in conjunction with set screws, secure the wedge members and prevent the sprocket's half members from tilting about the shaft element. The wedge members maintain a uniform pitch diameter of the sprocket's teeth by preventing contact between the half sprocket members.

Abstract: There is provided a clam shell shaped belt guide pulley having first and second curved halves which are hinged together. Each pulley half has curved inner and outer surfaces. The pulley is adapted to be placed on a large diameter shaft without the need to remove the shaft from the remainder of the machine. There is no supporting structure between the inner surfaces of the pulley halves and the shaft.

Abstract: Sprocket wheels for modular plastic link belts are made in two mating halves for expediting removal perpendicularly away from a coaxial drive shaft about which they are supported without disassembly of the shaft. To assure axial alignment and stability of the mating parts overlap joints between the parts are formed by securing together in surface contact laminar flange extensions from respective sprocket wheel halves joined in driving relationship about an inner shaft to form a completed sprocket wheel assembly. For critical use in food and chemical environments, the entire sprocket assembly is made of plastic, including binding clamps for holding the two mated flange surfaces of different halves together.

Abstract: A three-piece, all-plastic idler pulley assembly. There is a first unitary bell end portion having a first circular, inward-facing face with a concentrically-disposed, cylindrical shaft extending outward therefrom and perpendicular thereto. The cylindrical shaft has a concentric longitudinal bore therein. There is also a second unitary bell end portion having a second circular, inward-facing face with a concentrically-disposed, cylindrical projection extending outward therefrom and perpendicular thereto. The cylindrical projection is disposed within the longitudinal bore of the cylindrical shaft whereby the second circular, inward-facing, vertical face is disposed at the end of the cylindrical shaft perpendicular to the first inward-facing face and the second bell end portion is connected to the first bell end portion and spaced therefrom. A plastic cylindrical hub is rotatingly mounted on the cylindrical shaft between the first inward-facing face and the second inward-facing face.

Abstract: A split guide ring for use with a split sprocket which is mounted on a shaft and used to support and drive conveyor and drive chains.

Abstract: A chain wheel for conveyor installations with chain conveyor belts, and which chain wheel is mounted on the drive shaft (5) of the driving device for the conveyor belt. The chain wheel is designed in such a manner that it can be easily repaired and altered as to number of teeth, design of hub and number of tooth rims. It incorporates as a basic unit a pair of hub portions (1, 2) detachably connected against each other, between which, as a separate unit is clamped a tooth rim (3) comprising at least two sections 3a, 3b).

Abstract: A split pulley made of a resilient material which is held together by a circumferentially extending strap carried wholly within the body of the pulley.

Abstract: A split power transmission element, such as a sprocket, mountable on a driven shaft. A pair of substantially identical sprocket halves each include a pair of aligned, hollow, fastener sleeves extending diagonally through the plane of the sprocket. A pair of fasteners within the sleeves join the sprocket halves to each other and clamp the sprocket onto the shaft. The diagonal orientation of the fastener sleeves permits convenient disassembly of the sprocket from an upwardly located, axially displaced position. The sprocket halves are substantially identical and can be economically molded using a single mold. A keyway insert distributes driving forces throughout the sprocket hub and increases the maximum torque capacity of the sprocket.

Abstract: A tension or idler roller for a belt drive system has an outer roller for engaging a belt, an inner support body adapted to be affixed to a machine, and a rolling bearing between the outer roller and the support body. The support body is comprised of a pair of identical cup-shaped elements oriented either with their open ends toward one another or their closed ends toward one another, the shells having an eccentric mounting. The inner ring of the bearing may be a separate element or it may be formed in the shells.

Abstract: The invention proposes to form the flanges (11,12) of a driving pulley as a part of the driving shaft (10), for example by moulding the shaft (10) and the flanges (11,12) so as to constitute one unit, the portions (18,19) of the driving pulley being attachable between the said flanges (11,12).