Abstract: An electromagnet assembly for an electromagnetic apparatus has a ring member, a coil bobbin having an electrical wire wound a spool of the ring member, and a ring case. The ring member is disposed in an annular groove of the ring case. An opening is formed through the ring case adjacent to its closed end surface. A connector, which is disposed on the ring case and covers the opening, includes a case having a closed shape and a bottom, and a cap closing an open end of the case. Ends of the electrical wire and ends of a lead wire are joined in the connector. A projection portion is formed around a fringe portion of a first end surface of the cap and abuts an open end surface of the case. The cap is secured fixedly to the case after the projection portion is melted.

Abstract: In an electromagnetic clutch having drive and driven side clutch plates in which the drive side clutch plate is provided with a plurality of elongated holes circumferentially arranged at given intervals, a depression is formed by compressing and plastically press deforming each bridge portion positioned circumferentially between adjacent two of the elongated holes on an axial end surface of the drive side clutch plate facing the driven side clutch plate. Though tensile stress caused by belt tension is likely concentrated on the bridge portion, the depression, which causes higher hardness of the bridge portion, effectively serves to restrain occurrence of the fatigue failure.

Abstract: The invention relates to an electromagnetic friction clutch for arrangement within a drive train connecting a drive motor (2) and a vehicle door or a vehicle flap, the clutch (5) comprising a rotor part (16) which is provided with a friction lining (17) and is connected fixedly in terms of rotation to a first shaft (15) and on its side facing away from the friction lining (17) an electrical coil (19) is arranged, and an armature disk (14) which is connected fixedly in terms of rotation, but axially displaceably, to a second shaft (8) and which, with the clutch (5) in the connected state, is drawn against the frictional lining (17) of the rotor part (16) of the first shaft (15) and makes a frictional connection between the two shafts (8, 15).

Abstract: An electromagnetic clutch reduces clutch operating noise at a low cost by utilizing elastic members which are suited to a spring force of a leaf spring. An approximate nonagonal leaf spring has an outer ring portion, attachment portions connected to a hub, and connecting portions. Under the outer ring portion, securing portions of an armature are disposed. First elastic members are disposed at intermediate points of the securing portions, and a second elastic member is disposed in a gap between the leaf spring and the hub along an axial direction. When actuating the electromagnetic clutch, the leaf spring compresses the second elastic member, and when stopping the electromagnetic clutch, the armature collides with the first elastic member so that an axial position of the armature is secured.

Abstract: The subject invention improves the electrical connection in a clutch assembly for engaging a compressor in a vehicle air conditioning system. In accordance with the subject invention, a tab extends from the mounting plate and the second end of the ground lead is frictionally retained between the tab and the core winding housing. This is accomplished by turning a tab out of the plane of a mounting plate, placing the second end of the ground lead under the tab and bending the tab downwardly to clamp the second end of the ground lead between the tab and the core winding housing to frictionally retain the second end of the ground lead between the tab and the core winding housing.

Abstract: The subject invention improves the electrical connection in a clutch assembly for engaging a compressor in a vehicle air conditioning system. In accordance with the subject invention, a tab extends from the mounting plate and the second end of the ground lead is frictionally retained between the tab and the core winding housing. This is accomplished by turning a tab out of the plane of a mounting plate, placing the second end of the ground lead under the tab and bending the tab downwardly to clamp the second end of the ground lead between the tab and the core winding housing to frictionally retain the second end of the ground lead between the tab and the core winding housing.

Abstract: A magnet type fan clutch apparatus is formed of an electromagnetic clutch mounted on one driving shaft, and a magnet coupling operatively connected to the electromagnetic clutch. The magnetic coupling includes a permanent magnet rotary body to which a fan is fixed, and a disc having a conductor or a hysteresis member opposed to the permanent magnet rotary body with a narrow clearance left therebetween; and formed so that the permanent magnet rotary body and disc are rotated together or relatively owing to an attraction working between the permanent magnet and conductor. The magnetic coupling is formed so as to be ON/OFF controlled by the electromagnetic clutch, and a seal structure is provided between the disc and permanent magnet rotary body.

Abstract: In the disclosed electromagnetic clutch, a bent porion (15a) of a plate (15) comes into contact with an armature (6) attempting to move beyond a predetermined movable range, thereby restricting the movement of the armature (6). As a result, if an elastic member (14) is fused, a trouble is prevented which otherwise might be caused by the movement of the now-unsupported armature (6) beyond a predetermined movable range.

Abstract: A clutch pulley for selectively engaging a belt of a first device and a shaft of a second device, including a sheave member, an electromagnetic coil, a flex plate, and a ring member. The sheave member includes a sheave belt surface adapted to engage the belt and a sheave clutch surface. The electromagnetic coil is adapted to selectively create an electromagnetic flux. The flex plate includes a flex inner section concentrically coupled over the shaft, a flex outer section adapted to selectively move between two axial positions relative to the flex inner section based upon the presence of the electromagnetic flux, and a flex spoke section connecting the flex inner section and the flex outer section. The ring member is connected to the flex outer section and includes a ring clutch surface adapted to selectively engage the sheave clutch surface based upon the axial position of the flex outer section.

Abstract: In order to increase the transfer torque by improving the level of magnetic attraction between the friction surface of an armature and the friction surface of a rotor in an electromagnetic clutch, a magnetism blocking portion for blocking a flow of magnetism is formed to extend along the circumferential direction at an approximate middle position of a disk of the armature along the radial direction. In a similar manner, a plurality of magnetism blocking portions for blocking the flow of magnetism are formed to extend along the circumferential direction at the friction surface of the rotor of the electromagnetic clutch at varying positions set along the radial direction. A plurality of magnetic poles are formed with these magnetism blocking portions, and the facing area of a given outer circumference-side magnetic pole is set smaller than the facing area of the corresponding inner circumference-side magnetic pole by forming these magnetism blocking portions at specific, appropriate positions.

Abstract: A clutch pulley for selectively engaging a belt of a first device and a shaft of a second device, including a sheave member, an electromagnetic coil, a flex plate, and a ring member. The sheave member includes a sheave belt surface adapted to engage the belt and a sheave clutch surface. The electromagnetic coil is adapted to selectively create an electromagnetic flux. The flex plate includes a flex inner section concentrically coupled over the shaft, a flex outer section adapted to selectively move between two axial positions relative to the flex inner section based upon the presence of the electromagnetic flux, and a flex spoke section connecting the flex inner section and the flex outer section. The ring member is connected to the flex outer section and includes a ring clutch surface adapted to selectively engage the sheave clutch surface based upon the axial position of the flex outer section.

Abstract: A drive member (1) for a water pump of the cooling-water circuit of an internal combustion engine, with a drive wheel (7) and a shaft (4) which is coupled to the water pump, is proposed. According to the invention, for the transmission of torque between the drive wheel (7) and the shaft (4), an electromagnetically actuable friction-disk clutch (9, 10, 11, 12) and a second clutch device in the form of an eddy-current clutch (14) are provided, the latter taking up the shaft (4) when the friction-disk clutch is out of engagement. Moreover, a frictional shift clutch for a drive member of this type is proposed.

Abstract: A magnet type fan clutch apparatus is formed of an electromagnetic clutch mounted on one driving shaft, and a magnet coupling operatively connected to the electromagnetic clutch. The magnetic coupling includes a permanent magnet rotary body to which a fan is fixed, and a disc having a conductor or a hysteresis member opposed to the permanent magnet rotary body with a narrow clearance left therebetween; and formed so that the permanent magnet rotary body and disc are rotated together or relatively owing to an attraction working between the permanent magnet and conductor. The magnetic coupling is formed so as to be ON/OFF controlled by the electromagnetic clutch, and a seal structure is provided between the disc and permanent magnet rotary body.

Abstract: In an electromagnetic clutch, a rotor, an armature and a stator housing including an electromagnetic coil are assembled to a center hub through a bearing member. Therefore, by assembling the center hub to an engine crank shaft, an assembling operation of the electromagnetic clutch to a vehicle is finished. In addition, a stator plate fixed to the stator housing is fixed to an engine through a bushing made of an elastic material. Therefore, a vibration displacement of the stator housing relative to the rotor, generated due to vibration of the engine, can be absorbed.

Abstract: An electromagnetic clutch having an electromagnet, a rotational member mounted to undergo rotation, an armature selectively coupled to the rotational member for rotation therewith when the electromagnet is energized, and a ball bearing rotatably supporting the rotational member. The ball bearing has an inner race, an outer race, and a plurality of balls arranged in a plurality of rows each containing an odd number of the balls. The balls of the ball bearing are disposed between the inner race and the outer race so that each of the balls contacts the inner race at at least one point and contacts the outer race at at least one point.

Abstract: In an electromagnetic clutch having drive and driven side clutch plates in which the drive side clutch plate is provided with a plurality of elongated holes circumferentially arranged at given intervals, a depression is formed by compressing and plastically press deforming each bridge portion positioned circumferentially between adjacent two of the elongated holes on an axial end surface of the drive side clutch plate facing the driven side clutch plate. Though tensile stress caused by belt tension is likely concentrated on the bridge portion, the depression, which causes higher hardness of the bridge portion, effectively serves to restrain occurrence of the fatigue failure.

Abstract: Disclosed are a gas compressor and an air conditioning system in which an anomalous temperature rise in an electro-magnetic clutch is detected at an early stage to stop the operation of the gas compressor. A temperature sensor is mounted at a position in the vicinity of a portion of the electro-magnetic clutch which is subject to anomalous heat generation. When there is a rise in the temperature as detected by the temperature sensor, a driving circuit of the electro-magnetic clutch is interrupted before trouble is caused by an abnormally high temperature.

Abstract: A method for making an armature assembly is provided that reduces the level of acoustic noise during initial engagement of the armature, during slippage, and during disengagement. The armature assembly includes an armature disc, an annulus of sound damping material, and a hub assembly having a flexible spider with a web portion. The armature assembly is made by first forming the annulus of sound damping material with a plurality of angularly spaced molding tabs. The annulus is affixed to the web portion of the hub assembly using the molding tabs and is then compressed by securing the armature disc to the web portion such that one side of the annulus is disposed against the web portion and a second side of the annulus is disposed against the armature disc.

Abstract: A torque transfer device is provided that includes an input member for receiving torque from an external source. An output member is disposed radially inward of the input member to define a first torque transferring region therebetween. A second torque transferring region is also disposed between the input member and output member. A source of magnetic flux is operable to provide a first level of magnetic flux that transfers torque between the input and output members by activation of the first torque transferring region. The source of magnetic flux is also operable to provide a second level of magnetic flux that transfers torque between the input and output members by activation of both the first torque transferring region and the second torque transferring region. The torque transfer device substantially eliminates the “hard” or sudden engagement of conventional electromagnetic clutches.

Abstract: An automotive air conditioning compressor clutch eliminates all rivets and utilizes only one return spring. A hub with multiple radial teeth closely fitting into armature openings supports the armature plate concentric and parallel to a pulley friction disk. The armature is free to slide relative to the hub as the return spring is compressed. The thrust areas between the hub teeth and armature are large, which reduces compressive stress. The lower stress reduces the wear rate for both the all-metal and rubber torque cushion versions of the clutch.

Abstract: The invention provides an electromagnetic clutch that effectively reduces the shock noise produced during the coupling of an armature plate and a drive rotor, and furthermore, has a laminated body that can be provided at a low cost as an essential constituent element. The armature plate 34 of the electromagnetic clutch is a laminated body that comprises a plurality of thin metal plates 41, a plurality of fastening tongues 45 project from the inner diameter side of the friction plate 42 on the friction surface side, and these fastening tongues 45 are bent and surround the other laminated thin metal plates 41 so as to fasten them.

Abstract: The present invention aims to provide an electromagnetic clutch capable of decreasing the impact noise generated when the armature plate and the driving rotor are coupled. The present invention further aims to provide a compressor equipped with this electromagnetic clutch. An electromagnetic clutch in the present invention comprises a driving rotor including a coil, and an armature having an armature plate that is disposed facing this driving rotor and having the same axis of rotational thereas, and when a voltage is applied to excite coil, the end face of driving rotor and the armature plate are attached together by coil's magnetic force, thereby coupling driving rotor and armature. Armature plate comprises a plurality of metal thin plates (plate members) laminated together, and at least a part of the plate members being connected each other.

Abstract: An electromagnetic clutch assembly for selectively connecting a source of rotative power with a driven component having an input shaft rotatable about a shaft axis features a driven member mounted for rotational movement about the shaft axis. The electromagnetic clutch assembly includes an armature disk constructed and arranged to be drivingly connected with the driven component. The armature disk is stamped within an annular portion thereof to provide oppositely facing convex and concave surfaces, and a frictional material is fixedly disposed within the concave configuration of the convex and concave surfaces. The friction material and the driven member have gripping surfaces, which interengage when a magnetic coil assembly is energized.

Abstract: The present invention relates to an electromagnetic clutch device for a compressor used for air conditioners in vehicles and so forth. The object of the present invention is to provide an electromagnetic clutch device whose pulley can be downsized regardless of the outer diameter of a coil even when the so-called alignment is small. In order to achieve this object, an electromagnetic clutch device according to the present invention comprises a drive shaft forming a part of a compressor mechanism which is accommodated in a housing of the compressor and projecting through a nose of the housing; a drive rotor accommodating a coil for the electromagnetic clutch and rotatably supported on the circumference of the nose by means of a clutch bearing; an armature plate opposing the coil and connected to a projecting end of the drive shaft so as to rotate with the drive shaft; and a pulley fixedly attached to the drive rotor, wherein the pulley is arranged between the housing and the coil.

Abstract: To provide an electromagnetic coupling apparatus that is low in manufacture cost and superior in durability with high performance, the electromagnetic coupling apparatus including: a first rotary member constituting a magnetic circuit; a magnetically exciting coil provided to be relatively rotatable inside of the first rotary member; a yoke provided to be rotatable relative to the first rotary member for constituting a part of the magnetic circuit of said first rotary member; and a second rotary member provided to face the first rotary member in the axial direction and having a movable member provided to be movable in the axial direction for constituting a part of the magnetic circuit. The yoke is formed by laminating thin plates in the axial direction.

Abstract: An electromagnetic clutch comprises a clutch rotor having a flange portion, an armature opposed to the flange portion, and a ring exciting coil. The ring exciting coil generates a magnetic flux for attracting the armature to the flange portion when it is supplied with current. The flange portion is formed having outside slits and inside slits. A magnetic pole portion on the outer peripheral side and a magnetic pole portion on the inner peripheral side are formed between the outside slits and the inside slits. A step portion and a concave surface continuous with the step portion are formed in a region corresponding to the magnetic pole portion on the outer peripheral side. The step portion serves to restrain the magnetic pole portion from touching the armature when the magnetic flux is formed.

Abstract: In an electromagnetic clutch, a rotor, an armature and a stator housing including an electromagnetic coil are assembled to a center hub through a bearing member. Therefore, by assembling the center hub to an engine crank shaft, an assembling operation of the electromagnetic clutch to a vehicle is finished. In addition, a stator plate fixed to the stator housing is fixed to an engine through a bushing made of an elastic material. Therefore, a vibration displacement of the stator housing relative to the rotor, generated due to vibration of the engine, can be absorbed.

Abstract: An electromagnetically actuated power transmitting assembly has a cup shaped pulley structure mounted for rotation about the input shaft of a power driven device. The pulley structure has an outer annular driven portion for engaging an endless flexible driving element such that engine driven movement of the driving element rotates the pulley structure. The outer annular portion has ferromagnetic material along at least an internal diametrical periphery thereof to allow magnetic flux to flow therethrough. A one-piece flux carrier/mounting structure is formed from ferromagnetic material and has a mounting portion fixedly mounted to the power driven device and an annular flux carrier portion nested within the cup shaped pulley structure to allow the pulley structure to rotate relative to the flux carrier and to allow magnetic flux to flow therebetween. An annular magnetic coil for inducing a field of magnetic flux is fixedly mounted in the carrier portion.

Abstract: An electromagnetic clutch includes an electromagnet device housed in a rotor. The electromagnet device has a ring member having a containing chamber, a coil member having a bobbin and a coil element and housed in the containing chamber of the ring member, and a seal mechanism provided for enclosing the coil element in the containing chamber at a sealed-off condition. A desired seal mechanism is formed without using a molding resin. The productivity of manufacturing processes for the electromagnetic clutch may be increased by stopping use of a molding resin. Moreover, the proper insulation of the electromagnet device may be ensured by the desired seal mechanism.

Abstract: An armature for a selectively engageable and disengageable coupling and a method of making the armature are provided. The armature includes a substantially annular body that is disposed about a first axis. The body may be formed by stamping or fine-blanking. One side of the body is hardened through a nitriding process. A grinding wheel is then applied at an angle to the same side of the body along a diametrical line of the body extending perpendicular to the first axis. As a result, the body is configured so that the thickness of the body increases as the distance from the diametrical line increases. In particular, the thickness of the body varies along each cross-section taken along the line from a minimum thickness at the innermost portion of the cross-section to a maximum thickness at the outermost portion of the cross-section. The inventive armature reduces galling, and the resulting noise, that occur during burnishing of couplings incorporating the armature.

Abstract: The invention provides an electromagnetic clutch that effectively reduces the shock noise produced during the coupling of an armature plate and a drive rotor, and furthermore, has a laminated body that can be provided at a low cost as an essential constituent element. The armature plate 34 of the electromagnetic clutch is a laminated body that comprises a plurality of thin metal plates 41, a plurality of fastening tongues 45 project from the inner diameter side of the friction plate 42 on the friction surface side, and these fastening tongues 45 are bent and surround the other laminated thin metal plates 41 so as to fasten them.

Abstract: A friction clutch such as an electromagnetic clutch, in which a driving friction surface is formed on a rotor integral with a rotationally driven pulley and a driven friction surface in opposed relation to the driving friction surface is formed on an intermediate member pivotally mounted on a boss by a pin, is disclosed. When the rotor is in rotation, the armature portion of the intermediate member is attracted by an initial energizing means for generating a comparatively small force such as an electromagnetic coil so that the intermediate member is rotated around the pin. When the friction surface of the intermediate member is lightly pressed against the friction surface of the rotor, the friction force exerted tangentially to the contact surface causes the intermediate member to rotate further around the pin and generate a large force along the normal. Thus, the friction force is increased thereby making it possible to transmit a large power from the rotor to the boss through the intermediate member.

Abstract: The present invention aims to provide an electromagnetic clutch capable of decreasing the impact noise generated when the armature plate and the driving rotor are coupled. The present invention further aims to provide a compressor equipped with this electromagnetic clutch.

Abstract: A power transmission mechanism for power-transmittably coupling a rotating unit of a compressor (11) composed of a drive shaft (17), a rotating support (23) and a swash plate (27) with an engine (62), comprising a pulley (56) and an armature (58), both of which constitute a first rotating body provided on a side of the engine, a hub (57), which serve as a second rotating body coupled to the drive shaft of the compressor, and a spring (64), which serves as an elastic means for coupling the first and second rotating bodies. A spring constant of the spring (64) is set such that a resonant frequency (fR) determined by the spring constant and a sum of a moment of inertia of the rotating unit of the compressor and a moment of inertia of the second rotating body as dominant factors is made smaller than a minimum frequency (f1) of torque variation produced on the compressor and more preferably smaller than a minimum frequency (f2) of torque variation produced on the engine.

Abstract: In order to reduce an electromagnetic clutch in an axial size, a ring-shaped leaf spring connects an armature to a hub. The leaf spring has an outer ring portion connected to the armature, an attachment portion connected to the hub and located inner than the outer ring portion, and a connecting portion for connecting the outer ring portion and the attachment portion. A plurality of rivets of the armature are disposed at the outer ring portion. An embossed portion for generating an initial deflection on the leaf spring is disposed at an intermediate portion between the rivets in the circumferential direction of the outer ring portion.

Abstract: Device for transmitting the movement to a fan (1) for cooling the coolant in a motor vehicle, comprising movement generating means (3,21) on which the fan (1) is mounted by means of an idle support (1a), a first electromagnetic clutch (30), engagement/disengagement of which causes rotation of the fan at a number of revolutions equal to that of the movement generating means or at zero revolutions; a second clutch (60;160;260;360), engagement/disengagement of which causes rotation of the fan at a number of revolutions lower than that of the movement generating means or at zero revolutions; means (62) of the electromagnetic type for engaging/disengaging the second clutch, in which said first clutch (30) is supported in a position substantially adjacent to the fixed base (10) of the engine casing and said clutch (60) is supported by a fixed shaft (13) in a position substantially projecting from the base (10) of the engine.

Abstract: An electromagnetic clutch has a gear formed with a tubular part having a hollow portion into which a shaft is inserted. The tubular part is formed with a plurality of position restrainers each consisting of a pair of position restricting projections formed at a base end on an outer periphery thereof, and a plurality of slip stopper projections formed at a lead end thereof. An armature and a ring member are mounted on the shaft in such a manner as to oppose to the slip stopper projections. The armature is formed with a through hole for inserting the tubular part of the gear, and a projection that is fitted in a space between each pair of the position restricting projections. The ring member is made of an elastic polymer and has a radial thickness generally greater than a distance between the outer surface of the tubular part and a lead end of the projection of the armature mounted on the tubular part of the gear.

Abstract: An electromagnetic clutch has a field coil including an energizing coil, a shaft which is mounted inside the energizing coil and the field coil and is set rotatable about an axis thereof, a rotor which is non-rotatably mounted on the shaft at a position opposing the field coil, a gear which is rotatably mounted on the shaft, an armature which is mounted on the shaft on the side of the rotor and is set rotatable with the gear, and an O-ring made of a resilient material for setting the armature away from the gear toward the rotor due to a resilient force thereof when the energizing coil is excited. An outer circumference of the shaft at a position for engaging with the rotor is generally configured into a decagonal shape in cross section, and the contour of a through hole of the rotor for fitting the shaft has a generally decagonal shape in cross section.

Abstract: A ball bearing 36 supports a rotor 35 of an electromagnetic clutch 31 in such a manner that the rotor 35 can be rotated about the axis of the ball bearing 36. The ball bearing 36 includes an outer race 12, an inner race 13, a ball 14, and a retainer 15. The outer and inner races 12 and 13 are each formed in a circular-ring shape. The ball 14 is rollingably interposed between the outer and inner races 12 and 13. In the inner peripheral surface 16 and outer peripheral surface 17 of the outer and inner races 12 and 13, there are respectively formed grooves 12a and 13a each of which extends along the race peripheral direction and has an arc-shaped section. The grooves 12a and 13a are each formed in such a range in which their respective radii of curvature re and ri satisfy 1.0≦(re+ri)/Da≦0.9746 (Da/dm)−0.0304, where Da: the diameter of the ball, and dm: the mean value of the diameters of the inner and outer races of the ball bearing.

Abstract: The present invention relates to an electromagnetic clutch device for a compressor used for air conditioners in vehicles and so forth. The object of the present invention is to provide an electromagnetic clutch device whose pulley can be downsized regardless of the outer diameter of a coil even when the so-called alignment is small. In order to achieve this object, an electromagnetic clutch device according to the present invention comprises a drive shaft forming a part of a compressor mechanism which is accommodated in a housing of the compressor and projecting through a nose of the housing; a drive rotor accommodating a coil for the electromagnetic clutch and rotatably supported on the circumference of the nose by means of a clutch bearing; an armature plate opposing the coil and connected to a projecting end of the drive shaft so as to rotate with the drive shaft; and a pulley fixedly attached to the drive rotor, wherein the pulley is arranged between the housing and the coil.

Abstract: A bearing used for an electromagnetic clutch includes an inner race, an outer race, and a plurality of balls provided between the inner and outer races. The plurality balls are arranged in single row, and each of the balls contacts both inner and outer races at two contact points, respectively. Thus, even when the outer race inclines due to an external force, each ball continuously contacts both the inner race and the outer race at at least one point, respectively. Accordingly, the balls do not fall due to gravity, thereby preventing noise generated by balls falling and colliding with the races.

Abstract: The present application discloses a power actuator that has a motor having a rotatable motor output member and a clutch assembly. A stamped, cup-shape ferromagnetic coil casing has a generally radially extending base wall and an annular side wall extending generally axially from the base wall. An annular ferromagnetic flux intensifying washer is positioned adjacent to the base wall of the coil casing. An annular coil of electroconductive material is disposed within the casing with the side wall extending in surrounding relation with respect to the coil such that the field generated by the coil flows generally radially through the base wall and generally axially through said side wall. A ferromagnetic armature is in sliding relation with the annular coil and movable between an engaged position and a disengaged position.

Abstract: A spring plate member is connected to a hub. The spring plate member includes a plate spring portion generating a resilient force to separate an armature from a rotor, and an outer ring portion, which faces the armature. An elastic member is provided between the armature and the outer ring portion for connecting the armature directly with the outer ring portion. Thus, operation noises of the electromagnetic clutch and a compressor are efficiently reduced. Further, the axial dimension of elastic member can be made much smaller than that of the conventional cylindrical elastic member.

Abstract: An improved electric clutch for driving refrigeration compressors and the like includes an annular ferromagnetic annular armature that is connected with a drive shaft via the outer peripheral portion of an annular resilient disk the inner peripheral portion of which is connected with a rotor that in turn is connected with the drive shaft. The armature is normally biased in the direction of the rotor toward an inactive de-energized position in spaced relation relative to an annular driven member that is connected with the driven shaft. A stationary electromagnetic coil is mounted on the opposite side of the driven member from the armature, so that when the coil is energized, the armature is attracted toward an active energized position in frictional engagement with the driven member, thereby to cause the driven shaft to be driven by the drive shaft.

Abstract: A disk material is plastic-formed to form an inner cylindrical portion of a rotor and a cover member which covers an end side of the rotor. After that, the disk material is slit inwardly from an outside thereof in a radial direction of the disk material to form an outer cylindrical portion of the rotor and a pulley corresponding portion which will be the pulley. Finally, the pulley corresponding portion is plastic-formed to form a pulley groove. Thereby, even when the location of the pulley relative to the outer cylindrical portion are different, same processes can be applied to these different type pulley integrated rotors until the disk material is slit. That is, many different type pulley integrated type rotors can be manufactured with low cost while maintaining high concentric accuracy between the pulley and the rotor.

Abstract: In an electromagnetic clutch having a rotating component, groove portions (21a, 21b) are made on a surface of the rotating component to induce air flow during rotation of the rotating component. The air flow enhances radiation of heat from the electromagnetic clutch. It is preferable that the groove portion is formed at each of axial ends of a driving rotor or pulley (12) included as the rotating component in the electromagnetic clutch.

Abstract: An electromagnetic clutch and pulley assembly includes a clutch assembly, a pulley assembly having a pulley member drivable for rotation about a shaft axis by a flexible belt, and an electromagnetic coil assembly disposed adjacent to the pulley member. The pulley member is coupled to a shaft when the electromagnetic coil assembly is energized. The clutch assembly includes a hub, an armature disk, torsion transmitting structure and axially compressible resilient structure. The torsion transmitting structure can transmit torsional movement of the armature disk to the hub.