Abstract: Brushes (20, 21) which come into slidable contact with slip rings (23, 24) having power feeding terminals (51, 53) electrically connected to a power feeding side include extending portions (32, 36) extending in the radial direction of a field core (3). These extending portions (32, 36) are bent in a direction away from a coil bobbin (12). The third bent portions (32c, 36c) located at the ends of the extending portions are electrically connected to the terminal portions (10d) of coil terminals. An outer diameter R1 of a mounting recess portion (3a) which stores a power feeding device (5) of the field core (3) is smaller than an inner diameter R2 of the coil bobbin (12). This makes it possible to position the mounting recess portion (3a) at a distance H from the coil bobbin (12) in the field core (3) in the arrow A direction, thereby reducing the size of the rotating coil type electromagnetic clutch (1) in the arrow A-B direction.

Abstract: A drive device is provided with a housing 11 and an electromagnetic clutch mechanism 14 accommodated in the housing. The electromagnetic clutch mechanism 14 is provided with an armature 41 rotatably supported in the housing 11, a rotor 42 arranged to face the armature 41 and rotatably supported in the housing 11, and a coil 46. An annular magnet 44 is fixed on the outer circumference surface of the rotor 42. A sensor 15 arranged inside the housing 11 detects a polarity change of the magnet 44 in association with rotation of the rotor 42. The magnet 44 is provided with an annular wall portion 44b extending toward the armature 41 beyond a surface on which the armature 41 is in contact with the rotor 42 with respect to the axial direction. The annular wall portion 44b is spaced radially outward from the armature 41. The annular wall portion 44b prevents abrasion powder produced on actuation of the electromagnetic clutch mechanism 14 from being scattered.

Abstract: A rotor housing (2) has flanges (8) projecting to two sides in the directions of axes of rotors and having suction flow outlets for suction pipes (33) which are integrally connected to the rotor housing (2). The rotor housing (2), a collector housing (21), and the suction pipes (33) are integrally formed of aluminum alloy casting. The lower surfaces of the flanges (8) of the rotor housing (2) are used as attaching surfaces to be attached to the upper surface of a cylinder head.

Abstract: A tension apparatus having a mechanical section, storage unit, output torque calculation section, and exciting current calculation section is disclosed. The mechanical section has an electromagnetic brake driven by an exciting current to generate an output torque and applies a tension to a material in continuous form, which is being wound and stretched, in accordance with the output torque of the electromagnetic brake. The storage unit stores actually measured characteristics between an exciting current value and the output torque of the electromagnetic brake in advance. The output torque calculation section obtains the output torque of the electromagnetic brake in correspondence with an input tension instruction value. The exciting current calculation section obtains an exciting current value of an exciting coil, which is necessary to generate the output torque of the electromagnetic brake, by looking up the storage unit.

Abstract: In a power transmission apparatus, a torque limiter mechanism has a plurality of holding portions, a disc plate and a flange, and an elastic member. The plurality of holding portions are fixed to either one of a pulley and a hub and aligned substantially equidistantly in a circumferential direction. The disc plate and flange are provided to either one of the pulley and the hub and oppose the holding portions. The elastic member is frictionally connected to the holding portions and the disc plate and flange, and is fixed to the remaining one of the pulley and the hub. The elastic member has connecting portions and an elastic support. The connecting portions are frictionally connected to the holding portions and the disc plate and flange, and correspond in number to the holding portions.

Abstract: A tension apparatus includes a mechanical section, signal output section, smoothing circuit, maximum value holding circuit, constant current driving circuit, and discharge circuit. The mechanical section has an electromagnetic brake driven by an exciting current to generate an output torque and applies a tension to a material in continuous form which is being wounded and stretched by the output torque of the electromagnetic brake. The signal output section repeatedly outputs a PWM (Pulse Width Modulation) signal having a duty ratio corresponding to an input tension instruction value before and after a predetermined stop period. The smoothing circuit smoothes the PWM signal from the signal output section. The maximum value holding circuit holds a maximum voltage value of the smoothed PWM signal. The constant current driving circuit supplies an exciting current corresponding to the held maximum voltage value to the electromagnetic brake.

Abstract: An electromagnetic coupling device includes a damper rubber member to mitigate the sound generated during attraction of the armature to the rotor. The spring constant of the damper rubber member is increased by increasing the contact surface of the damper rubber member at a head portion of the torque transmission pin.

Abstract: A tension device for winding yarn includes a bracket with an inclined face and a braking member accommodated in the bracket. A rotary shaft protrudes from the center of the bracket. A tubular member has a through-hole for the rotary shaft. A forward guide member includes two hub members mounted on the axial end of the rotary shaft with a yarn winding portion joining the hub members.

Abstract: In an electromagnetic clutch, an annular exciting coil having a pair of connecting portions at its intermediate winding portion, a coil bobbin, having a first coil holding groove for holding the exciting coil, and a coil cover, having a second coil holding groove for holding the exciting coil projecting from the coil bobbin, are stored in a yoke to expose a storing portion formed on the coil cover and having a pair of through holes from which the connecting portions of the exciting coil are led out. A temperature fuse is stored in the storing portion and has a pair of lead wires. A pair of intermediate terminals are arranged to oppose each other through a predetermined distance, and have lead press-insertion grooves where the lead wires of the temperature fuse are to be press-inserted, and coil press-insertion grooves where the connecting portions of the exciting coil led out from the through holes are to be press-inserted. A terminal cover fixes the intermediate terminals.

Abstract: A compact, inexpensive electromagnetic spring clutch includes forming supporting bearing surfaces made of synthetic resin rotary members, in a magnetic excitor. Cylindrical magnetic pole parts are formed in the first core and second core and the inner surfaces of these magnetic pole parts are made into bearing surfaces.

Abstract: An accommodation section 22 is disposed integrally with a coil bobbin 20. A winding start portion 4a and a winding end portion 4b of an excitation coil 4 are forced into the accommodation section 22, a diode 24 is accommodated, and they are electrically connected through two terminals 27A and 27B. Coil engagement grooves 30a and 30b into which the winding start portion 4a and the winding end portion 4b are fitted, lead engagement grooves 31a and 31b and terminal engagement grooves 32a and 32b into which the terminals 27A and 27B are fitted are made in the inner bottom surface of the accommodation section 22. The terminals 27A and 27B have grooves into which the winding start portion 4a, the winding end portion 4b and the leads 24a and 24b are fitted, respectively, and lead wires 26 on the power source side are connected, respectively.

Abstract: The electromagnetic coupling device 1 has a one piece armature hub (8) with a central bore attached to a compressor drive shaft (3). Flanges (8b) extend tangentially from the boss (8a) of the armature hub (8). The peripheral edges of the boss (8a) and the flanges (8b) are bent in an axial direction to form a peripheral wall (8c). A portion of the peripheral wall (8c) on the ends of the flanges (8b) form the chamber walls (8d) of damper covers (8e). The chamber walls (8d) have an opening on the side of the damper chamber facing the boss (8a). Rubber dampers (10) are compressed and mounted in each damper cover (8e). Torque pins (11) are mounted in the rubber dampers (10), pass out of the damper covers (8e) and are staked to the armature (12). Projections (8i) can be formed in the flanges (8b) by a press and limit movement of the armature (12) away from the rotor (6).

Abstract: A magnetic coupling includes a cylindrical housing, a spindle, an adjusting plate, two pairs of permanent magnet discs, two hysteresis material discs, and a screw member. The spindle is rotatably supported at its axial position by the housing. The adjusting plate is rotatably supported by the spindle to partition an interior of the housing into two sections in a direction of the spindle. The two pairs of permanent magnets are provided in the two corresponding sections to respectively oppose each other. One of each pair of permanent magnet discs is fixed in the housing and the other thereof is fixed to the adjusting plate. Each permanent magnet disc has magnetic poles with polarities that alternate in a circumferential direction. The hysteresis material discs are fixed to the spindle and arranged between the corresponding pairs of permanent magnet discs at a predetermined gap. The screw member fixes the adjusting plate to the housing.

Abstract: An armature assembly (4 or 15) for an electromagnetic coupling device has a stop plate (9), rubber dampers (11) and an armature (12). Stop plate (9), which is formed in a press from a single steel plate, has a boss (9b), flanges (9c) and a periphery wall (9a). The periphery wall (9a) reinforces the stop plate (9) and forms damper covers (9e) on the ends of the flanges (9c). The damper covers (9e) have a wall surface (9d) that surrounds the damper chamber except for an opening on one side of the damper cover facing toward the boss (9b). A rubber damper (11) with a torque pin (10) is mounted in each damper cover (9e). An armature (12) is secured to the torque pins (10) by staking. The opening in one side of the damper cover permits the rubber damper 11 adjacent to the opening to move toward the torque pin (10) when that portion of the rubber damper is subjected to a tension force. This movement of the rubber damper (11) reduces the maximum stress in the damper and increases damper life.

Abstract: An electromagnetic spring clutch includes a stator, an excitation coil, an input-side rotating member, an output-side rotating member, a coil spring, and a rotor. A central hole is formed in the stator. The central hole has an inner circumferential surface formed by a plurality of magnetic pole segments that mesh each other alternately through a gap in circumferential and axial directions. The excitation coil is accommodated in the stator. The input- and output-side rotating members are made of a non-magnetic member and formed with fitting portions and coil tight-winding surfaces. The fitting portions respectively support the two open end portions of the central hole of the stator, and the coil tight-winding surfaces have end portions that oppose each other in the central hole. The coil spring is wound on the coil tight-winding surfaces of the two rotating members and has one end hooked by the input-side rotating member.

Abstract: An electromagnetic coupling apparatus includes an armature hub, a leaf spring, an armature, a rubber stopper, a fixing member, a rubber vibration insulator, a rotor, an electromagnetic coil, and a field core. The armature hub is fixed to the rotating shaft of a unit and has a flange portion formed with a through hole. The fixing member is fixed to the armature and has a trunk portion and a head portion formed with an annular wall portion on its outer circumference. The rubber vibration insulator is disposed between a side surface of the flange portion of the armature hub and the head portion of the fixing member, and is constituted by a cylindrical portion and a disk portion. The rotor opposes the armature through a first gap of a predetermined size.

Abstract: The armature assembly (9 or 17) includes a hub (10 or 19) adapted to be connected to and rotate with an input shaft (8 or 18). The hub (10 or 19) includes a flange (10a or 19a) connected to a composite material armature support plate (12 or 21). Rubber dampers (15 or 23) are molded to rivets (14 or 24) and are pressed into cylindrical peripheral walls (12a or 21b) of damper holder sections (13 or 22). The rivets (14 or 24) are staked to an armature (16 or 25). The rubber dampers (15 or 23) bias the armature (16 or 25) into contact with surface of a stopper (10e or 21g) when an electromagnetic clutch (1) is not energized and a space (G or G.sub.2) is formed that extends axially from the armature (16 or 25) to the armature support plate (12 or 21) and radially outward from the stopper (10e or 21g).

Abstract: Rotation slip between the rotor and the armature of an electromagnetic clutch results in the exciting current I in the electromagnetic coil decreasing locally abruptly to form a unique waveform. The locally abruptly rising variations in the current is taken out as a locally abruptly variation (an alternating current component) in an inverted and amplified voltage, and the alternating current component is applied to a comparing circuit (400). The instantaneous value of the alternating current component is compared with a threshold which rises as the rotational speed of the rotor becomes higher, and while the instantaneous value exceeds the threshold, a comparison output is outputted. The comparison output is applied to a continuous waveform confirming circuit (500), and if the predetermined number of comparison outputs are detected with a predetermined time after a first comparison output has been generated, it is determined that a rotation slip has occurred.

Abstract: An electromagnetic clutch includes a rotor assembly constituted by a pulley portion and a rotor portion. The pulley portion has a pulley portion on an outer circumferential side, is axially supported on a driven shaft to be rotatable, and is designed to receive a driving force from a driving shaft. The rotor portion has an armature on a side of the driving shaft. The armature is selectively friction-engaged by magnetic attraction. The rotor portion of the rotor assembly is formed by casting to have an uneven surface shape constituted by a plurality of projections on its outer circumferential surface. The synthetic resin pulley portion is integrally coupled to the outer circumferential surface of the rotor portion by insert molding.

Abstract: In a fluid pump, a pair of rotors having different rotation phases and designed to come into slidable contact with each other are rotatably contained in a rotor housing so as to be brought into slidable contact with a housing inner wall, and a large arcuated surface having the same radius of curvature as that of a housing inner circumferential surface and a small arcuated surface having a radius of curvature obtained by subtracting a radius of the large arcuated surface from a distance between axes of the rotors are formed on an outer circumferential surface of each of the rotors. A transitional surface crossing a virtual boundary line extending from a rotor center at an angle of 45.degree.