A graphite crucible for electromagnetic induction-based silicon melting and an apparatus for silicon melting/refining using the same, which performs a melting operation by a combination of indirect melting and direct melting. The crucible is formed of a graphite material and includes a cylindrical body having an open upper part through which a silicon raw material is charged into the crucible, and an outer wall surround by an induction coil, wherein a plurality of first slits are vertically formed through the outer wall and an inner wall of the crucible, and a plurality of second slits are vertically formed from an edge of the disc-shaped bottom of the crucible toward a center of the bottom.

A method for refining and casting metals and metal alloys includes melting and refining a metallic material and then casting the refined molten material by a nucleated casting technique. The refined molten material is provided to the atomizing nozzle of the nucleated casting apparatus through a transfer apparatus adapted to maintain the purity of the molten refined material. An apparatus including a melting and refining apparatus, a transfer apparatus, and a nucleated casting apparatus, in serial fluid communication, also is disclosed.

An electromagnetic induction melting furnace to control an average nominal diameter of the TiB2 cluster of the Al—Ti—B alloy includes a main body containing the melted alloy; and a multi-layer coil disposed on the main body, wherein a frequency of the alternative current of each coil of the multi-layer coil is different, and the alloy is heated by inducing a magnetic field generated by the alternative currents. The selection of the frequency and the changeable magnetic field may reduce the cohesion force between the TiB2 grains of the Al—Ti—B alloy to control the average nominal diameter of the TiB2 cluster.

An electromagnetic induction melting furnace to control an average nominal diameter of the TiC cluster of the Al—Ti—C alloy includes a main body containing the melted alloy; and a multi-layer coil disposed on the main body, wherein a frequency of the alternative current of each coil of the multi-layer coil is different, and the alloy is heated by inducing a magnetic field generated by the alternative currents. The selection of the frequency and the changeable magnetic field may reduce the cohesion force between the TiC grains of the Al—Ti—C alloy to control the average nominal diameter of the TiC cluster.

An electrode for a resistance analytical furnace has a crucible-engaging surface and an end spaced from the crucible-engaging surface having a plurality of grooves formed therein. A manifold mounted on the end of the electrode defines a dust recovery plenum and includes an outlet communicating with the plenum for coupling to a vacuum source to remove debris from the electrode. The improved electrode and electrode cleaning manifold positioned on the electrode provides a turbulent airflow for removal of dust and debris from an analytical furnace.

In one aspect, the invention is directed to a decoupler assembly for between an endless drive element and a shaft. The endless drive element may be, for example, an accessory drive belt from a vehicular engine. The shaft may be, for example, the input shaft of a belt-driven accessory, such as an alternator or a compressor. The decoupler assembly includes a hub that mounts to the shaft, a pulley that is rotatable with respect to the hub, a dampening spring and a clutch member. A part of the pulley is supported on a pulley support surface on the hub. There is a gap between the pulley and the pulley support surface. The gap has lubricant therein to facilitate sliding between the pulley and the pulley support surface. By eliminating the use of a polymeric bushing between pulley and the hub, there are several advantages that are provided.

In a steering system that includes: an intermediate shaft on a steering wheel side; a pinion shaft on a steered wheel side; and a cross joint by which the intermediate shaft and the pinion shaft are rotatably connected to each other on a plane intersecting with each of the shafts, and that steers steered wheels by transmitting steering torque of a steering wheel from the intermediate shaft to the pinion shaft, a weakened portion is formed in a joint spider of the cross joint. The weakened portion can be identified in advance as a portion that breaks first. This makes it possible to realize a failure mode in which a vehicle is able to run by itself for a certain period of time after a failure.

Structure of a cross universal joint is achieved in which the fact that an excessive torque was applied to a universal joint due to a collision accident or mishandling can be easily determined afterwards. Protrusions 20, which are straight lines as seen from the outside surface sides of linking arm sections 15c of a yoke 12c, are formed on the outside surfaces of the linking arm sections 15c. When an excessive torque acts and the linking arm sections 15c are plastically deformed, the protrusions 20 change from a straight line to a non-straight line. From this change it is possible to easily confirm that an excessive torque has been applied to a cross universal joint that includes this yoke 12c. Moreover, when the space between the inside surfaces of the linking arm sections 15c is taken to be D, and the length in the axial direction of the linking arm sections 15c is taken to be L, the dimensions of the parts of the yoke 12c are regulated so that the relation 3

A coupling means (10) provided with a first member (20) suitable for being fastened to a first rotary part (2) and with a second member (30) suitable for being fastened to a second rotary part (3), the first member (20) being provided with a first diaphragm (22) and the second member (30) being provided with a second diaphragm (32) that is secured to the first diaphragm (22). An emergency torque transmission device comprises at least one bayonet system including a protuberance (50) secured to one member (30) and co-operating with an angled groove (60) secured to the other member (20) by being inserted in the angled groove (60) by a thrust-and-rotation movement, in the absence of said breakage said coupling means (10) including both axial clearances in compression (70') and in translation (70″) and also circumferential clearance between each protuberance (50) and walls defining the corresponding angled groove (60).

A starting device of a spark-ignition multi-cylinder engine is provided. The device includes a multi-cylinder engine body having cylinders, fuel injection valves, ignition plugs, an intake valve drive mechanism for opening and closing intake valves, a hydraulic variable valve phase mechanism for changing a close timing of each intake valve, an engine-driven hydraulic pressure supply source for supplying a hydraulic pressure, and a start controller for controlling the fuel injection valves, the ignition plugs, and the variable valve phase mechanism. When the supplied hydraulic pressure is below a predetermined pressure, the variable valve phase mechanism locks the close timing. When an engine temperature in an engine-start is high, the start controller retards a fuel injection timing of the cylinder on intake stroke at an engine stopped timing and retards an ignition timing thereof. The start controller does not retard the close timing of the intake valve until the engine-start completes.

An input shaft assembly is movable along an axis to absorb external impact loads. A biasing member exerts an axial load in a direction counter to potential impact loads. A stop is provided to control the application of biasing loads to control application of such axial load.

A torque limiting device, particularly for power transmission elements, is provided. The torque limiting device includes a first connecting member and a second connecting member, which is connected rotatably to a driven element. The first connecting member includes a motor driving disk and the second connecting member includes a sliding disk, and further includes a pin supporting body which comprises a drum that is assembled on the second connecting member and includes a plurality of radial holes, each one of which accommodates a pin that is pressed, toward the center of the drum, by elastic means, and abuts, with at least one of its faces which is inclined with respect to the central rotation axis of the second connecting member, against at least one corresponding abutment face.

A vibration damper, including a cover plate with an annular portion, and a spring portion including spring retaining portions forming respective spaces and a spring blocking portions including respective protrusion segments and respective tab segments including respective portions of an edge of the cover plate and having a same first thickness. The damper includes springs at least partially located in the respective spaces, and having respective longitudinal ends, and a second cover plate or output flange connected to the cover plate. The springs are arranged to transmit torque to the cover plate. The respective protrusion segments have a same second thickness and include respective protrusions. Respective first portions of the longitudinal ends of the springs are engaged with the respective protrusions. Respective second portions of the longitudinal ends of the springs are engaged with the respective tab segments.

A flexible shaft coupling demonstrates a high performance in transmitting torque and accommodating positional deviations, and is yet highly durable. A first elastomer member (82) having a relatively high rubber hardness is circumferentially interposed between a first claw (32) of a first shaft coupling member (20) and a second claw (62) of a second shaft coupling member (50), and a second elastomer member (84, 86) having a lower rubber hardness than the first elastomer member is interposed between a surface portion (end surface) (30) of the first shaft coupling member (20) and the second claw (62) and/or between a surface portion (end surface) (60) of the second shaft coupling member (50) and the first claw (32).

A constant velocity joint including an outer race having inner and outer surfaces, the inner surface including a plurality of outer bail tracks. The constant velocity joint also includes an inner race having a plurality of inner ball tracks which correspond to the outer ball tracks, a ball cage disposed between the outer race and the inner race, a plurality of balls arranged within the ball cage and contacting the outer ball tracks and the inner ball tracks. A damping assembly is connected to the outer race.

A torque fluctuation absorber includes a first rotating member, a second rotating member arranged coaxially with the first rotating member, a control plate arranged between the first rotating member and the second rotating member in an axial direction and engaging non-rotatably with the second rotating member, a thrust member arranged between the first rotating member and the control plate in the axial direction, engaging with the first rotating member in an axially movable and non-rotatable manner, and slidably making contact with the control plate, and an elastic member arranged between the first rotating member and the thrust member in the axial direction, supported by the first rotating member and pressing the thrust member against the control plate.

A fixed type constant velocity universal joint has pairs of track grooves, each pair forming a wedge angle (α). The wedge angle (α) includes a wedge angle (α0) formed, when an operating angle is 0°, with respect to each of torque transmitting balls arranged in a joint center plane, and opening to the same side in an axial direction for all pairs of track grooves. Further, the pairs of track grooves are mirror-image symmetrical with each other when the operating angle is 0°.

A driveshaft containment system and a method of its use. In preferred embodiments, the invention takes the form of a two component system including a first component mounted to a device such as a differential housing, coupled to driveshaft, and a second component comprising a tubular driveshaft containment housing. A driveshaft containment ring is preferably mounted to the forward end of the tubular housing which in turn is provided with a mechanism at its rearward end for rotationally engaging and disengaging the first component. The first and second components are also provided with a mechanism for preventing relative rotational movement of the first and second components while engaged with one another.

A shaft portion of a joint outer ring where projections extending in an axial direction are provided is press-fitted into a hole portion of a hub wheel to thereby form recesses by the projections in an inner diameter surface of a shaft fitting hole of the hub wheel, by which a recess-projection fitting structure is constructed. An entire area of fitting sites of the projections and the recesses are brought into close contact. Moreover, a bolt member is fastened in a bolt hole provided in the shaft portion of the joint outer ring after the construction of the recess-projection fitting structure, which restricts separation between the hub wheel and the joint outer ring. As the bolt member, if an outer diameter of a seating surface thereof is d1 and a shaft diameter is d2, a bolt member satisfying a relational expression of 2.3≦(d1/d2)2≦4.9 is used.

A device for damping vibrations in a drive train, in particular for plug screws in the pulp and paper industries. The device is principally characterized in that a cylindrical shaft, preferably designed as a hollow shaft, is provided, wherein the cylindrical shaft is arranged between the halves of a coupling and at least one ring having friction surfaces is arranged around the cylindrical shaft. Stick-slip vibrations that occur can thereby be favorably eliminated, and thus the gearbox and the motor of the drive train can be protected.

A variable valve actuating apparatus includes: a first rotary member which includes a rotor fixed to one of the inner cam shaft and the outer cam shaft, and a receiving chamber formed within the first rotary member, and which is arranged to be rotated in an advance angle direction or in a retard angle direction relative to the drive rotary member by a hydraulic pressure selectively supplied to or drained from the advance angle operation chamber and the retard angle operation chamber; and a second rotary member fixed to the other of the inner cam shaft and the outer cam shaft, rotatably received within the receiving chamber of the first rotary member, and arranged to be rotated relative to the first rotary member and the drive rotary member within a predetermined angle range.

A variable valve actuating apparatus includes: a first lock recessed portion; a first lock member; a second lock recessed portion formed in the second rotary member's side; a second lock member; a first lock passage arranged to supply the hydraulic fluid, and thereby to move the first lock member out of the first lock recessed portion; and a second lock passage arranged to supply the hydraulic fluid, and thereby to move the second lock member out of the second lock recessed portion, at least a part of the first lock recessed portion and at least a part of the second lock recessed portion being disposed at a position to be projected in an axial direction when the first lock member and the second lock member are in the lock state.

The invention relates to a gear wheel pump with two meshing gear wheels which are rotatably mounted within a pump housing by means of a driven driveshaft and a crankshaft journal and which form a pumping channel system between a pump inlet and a pump outlet. Several gaps are formed between the pump housing, the gear wheels, the driveshaft, and the crankshaft journal. One of the gaps between the driveshaft and one of the gear wheels contains means for the rotationally fixed connection of the driveshaft to the gear wheel. In order to prevent leakages penetrating to the connecting means, according to the invention the gap between the driveshaft and the gear wheel is sealed, with respect to the front faces of the gear wheel, by means of a sealant.

A rotational vibration damper includes a primary side (32) and a secondary side (46) which is rotatable with respect to the primary side (32) around an axis of rotation (A) against the action of a damper element arrangement (28). At least one damper element unit (42) of the first group (70) and at least one damper element unit (42') of the second group (70') are pre-loaded, and the primary side (32) and the secondary side (46) are pre-loaded in a basic relative rotation position with respect to one another. Proceeding from the basic relative rotation position of the primary side (32) with respect to the secondary side (46), a pre-loading path (V, V') of at least one pre-loaded damper element unit (42) is shorter than a maximum relative rotation path of the primary side (32) with respect to the secondary side (46).

A rotation transmitting apparatus includes a first shaft on which multiple external teeth are formed so as to be arranged in a circumferential direction, and a second shaft in which multiple internal teeth are formed so as to be arranged in the circumferential direction, the second shaft being fitted to the first shaft so as to be slidable relative to the first shaft in the axial direction and so as to be engageable with the first shaft in a rotational direction through the use of the external teeth and the internal teeth. A protrusion is formed on the tooth flank of one of the external tooth and the internal tooth, the protrusion being projected toward the corresponding tooth flank of the other of the external tooth and the internal tooth. The protrusion is made of a resin that is more elastically deformable than the tooth flank.

An aluminum alloy propeller shaft including a tube made of an aluminum alloy, and a pair of yoke members made of an aluminum alloy, the yoke members including cylindrical base portions friction-welded to opposite end portions of the tube, each of the yoke members including a tip end portion having a pair of bearing retaining holes aligned with each other in a radial direction of the base portion. Variation in length between a central axis of the bearing retaining holes in one of the yoke members and a central axis of the bearing retaining holes in the other yoke member with respect to a reference length is set within a range of from +2.0 mm to −2.0 mm. A friction welding process of producing an aluminum alloy propeller shaft, including a friction step, a position displacement detection step, a rotation stop step and an upset step.

A joint in the form of a counter track joint is disclosed that comprises a joint outer part with first outer ball tracks and second outer ball tracks; a joint inner part with first inner ball tracks and second inner ball tracks; wherein first aperture angles are respectively formed between tangents to contact points of a ball with the first outer ball track and with the first inner ball track, and second aperture angles are respectively formed between tangents to contact points between a ball with the second outer ball track and with the second inner ball track. The first aperture angles of the first track pairs open towards a first side of the joint, and the second aperture angles of the second track pairs open towards a second side of the joint. Outer axial play is provided between the joint outer part and the ball cage. Inner axial play is provided between the ball cage and the joint inner part. Axial play permits relative axial displacement of the joint inner part with respect to the joint outer part.

A driveline shield system having a cap disposed to releasably engage a bearing mounted adjacent a drive shaft. The cap supports a tubular guard or shield in a coaxial position relative to the drive shaft. One or more lugs on the bearing are disposed to seat in corresponding slots formed in the cap. When the lugs are seated in the slots, rotation of the cap relative to the bearing causes the bearing and the cap to engage one another. A U-shaped clip is pivotally mounted to the cap and rotatable between a first position in which the clip extends into the slot and secures the lugs in engagement with the cap and a second release position in which the clip is retracted from the slot, thereby permitting relative rotation between the cap and bearing.

A combined CV joint boot and inner seal includes a boot portion having a first end and a second end and having a shaft sealing portion at the first end for sealing with a first shaft of the CV joint. A front can sealing portion is positioned at the second end of the boot portion. An inner seal portion extends generally inwardly towards the CV joint longitudinal axis to block lubricant from migrating into the interior of the boot portion.

A wheel supporting device includes: a hub unit that has a rotary ring having a first spline on its axially inner end face; and a joint that has an outer ring having a second spline, meshing with the first spline, on its axially outer end face. At least one projection included in a plurality of projections of the first spline projects in the axial direction by a larger amount than the remaining projections of the first spline. When a crest of the at least one projection contacts a crest of one of projections of the second spline, a play is caused between the rotary ring and the outer ring due to the at least one projection that works as a fulcrum.

In a scroll compressor of the present invention, a fixed scroll 11 and an orbiting scroll 12 are meshed with each other such that spiral laps of the fixed scroll 11 and the orbiting scroll 12 inwardly face each other, an Oldham ring 26 is provided between the main bearing member 19 and the orbiting scroll 12, and a key portion of the Oldham ring 26 is inserted into a key groove 19a of the main bearing member 19. Grooves 19b are formed in Oldham ring 26 sliding surfaces on both sides of the key groove 19a. According to this configuration, the Oldham ring 26 and the main bearing member 19 can be restrained from coming into contact with each other in the vicinity of the bearing key groove 19a, and restrained from vibrating, and it is possible to provide an inexpensive scroll compressor of low noise.

A coupling for connecting a rotating tube cleaning shaft to a tube cleaning machine where high pressure fluid is pumped through the coupling, where the coupling is sealed to contain the high pressure fluid, and where a machine driven rotary flexible shaft passes through the coupling.

A damper device configured with an input element, an intermediate element to which power is transferred from the input element through a first elastic body, and an output element to which power is transferred from the intermediate element through a second elastic body. One of the output element and the intermediate element has a protruding portion projecting in an axial direction. The other one of the output element and the intermediate element has a cutout portion corresponding to the protruding portion. The protruding portion has a restricting portion that is engaged with the cutout portion in a rotation direction so as to restrict rotation of the intermediate element relative to the output element, and a support portion that is engaged with the cutout portion so that the intermediate element is supported by the output element in a radial direction.

A lock-up device for a fluid coupling suppresses vibration caused by coil springs. The lock-up device includes an input rotation member, an output rotation member, a plurality of first elastic members, and a float member. The plurality of first elastic members are compressed in a rotational direction by the relative rotation of the input rotation member and the output rotation member. The float member is rotatable relative to the input rotation member to cause two of the first elastic members to act in series in a circumferential direction.

A device for generating limit torque with a function of yielding a torque change in real time includes a spring, a rotating portion having a cam surface formed therein, a transmitting portion transmitting an elastic force of the spring to the cam surface, a fixed portion with respect to which the relative rotation of the rotating portion is generated, and a limit-torque control portion provided to the fixed portion so as to control limit torque of the rotating portion by adjusting the elastic force of the spring. In the device, the limit-torque control portion controls the limit torque of the spring by changing the elastic force of the spring in real time.

A propshaft assembly includes an axle flange, a propshaft, and a damper. The propshaft includes a prop flange, which may be mated to the axle flange for common rotation therewith. The damper includes an outer mass that annularly surrounds the prop flange. The damper is press-fit onto one of the prop flange and a flange pilot, such that the damper is attached directly to the propshaft without fasteners.

A phase control apparatus in a variable cam timing (VCT) system of an engine is described herein. The phase control apparatus includes a locking pin coupled to a vane, the locking pin extending into a locking pin recess in a cover plate in a locked configuration, the locking pin and locking pin recess having a backlash and a housing at least partially enclosing the vane and spaced away from the vane forming a gap in the locked configuration.

A valve timing control device includes: a vane rotor having a plurality of vanes; a housing having the vane rotor inside so that an advance chamber is formed on one side of each vane and a retard chamber is formed on the other side; a lock pin inserted in a cylinder provided in the vane and moves to a lock position and to an unlock position; and a feeding passage for feeding oil into the cylinder from the retard chamber adjacent to the vane provided with the cylinder to make the lock pin move to the unlock position, and controls an oil supplying unit to supply oil to each retard chamber, wherein a flow passage cross sectional area of the branch passage connected with the retard chamber linking with the cylinder is larger than a flow passage cross sectional area of the branch passage connected with the other retard chamber.

A multi-legged apparatus enables a multi-legged robot to provide a natural motion, and includes a body portion comprising a body, a front leg portion comprising a front fixing portion fixed to the body, and a front rotating portion rotatably connected to the front fixing portion, a rear leg portion connected to the body and a rear leg portion comprising a rear rotating portion rotatably connected to the rear fixing portion, and a first link rotatably connected, at both ends, to the front and rear rotating portions, respectively. The body portion additionally includes a driving portion which rotates one of the front and rear rotating portions. By employing the first link and the driving portion, the body of the multi-legged robot is moved to and fro and left and right naturally in accordance with the movement of the legs, in a similar pattern as that generally shown in actual multi-legged animals.

An in-line coupling device for a motor driven agricultural system utilizes less metal components while optimizing torque transfer. The device comprises a puck having a plurality of outwardly extending arms, a first shaft hub having outwardly extending flanges adapted to seat between a pair of the plurality of outwardly extending arms, and a second shaft hub having outwardly extending flanges adapted to seat between a pair of the outwardly extending arms.

A pusher assembly for a stent delivery device includes a distal end of an elongate member and a stent-engaging member having proximal and distal ends. The proximal end of the stent-engaging member is mechanically coupled to the distal end of the inner member by a connector, or the proximal end of the stent-engaging member is at least partially inside the distal end of the elongate inner member. The stent-engaging member includes a portion that radially outwardly extends towards the distal end of the stent-engaging member, or the stent-engaging member includes a portion that radially outwardly extends towards the distal end of the stent-engaging member. The stent-engaging member is configured to move a stent when distally advanced and configured to not move a stent when proximally retracted. A stent delivery device includes an elongate outer member, an elongate inner member coaxially positioned within the outer member, and the pusher assembly.

In an electrically-driven valve timing control apparatus employing a housing and a cover member axially opposed to each other, a cylindrical-hollow motor output shaft is installed in the housing, and configured to rotate relative to the housing by electricity-feeding to the electric motor, and also configured such that lubricating oil is supplied into the motor output shaft. A plug is fitted to the inner periphery of an axial opening end of the motor output shaft for suppressing a leakage of lubricating oil from the motor output shaft to the outside. One of two opposing faces of the cover member and the plug is formed with a protruding portion configured to prevent the plug's slipping out of the axial opening end. A part of the inside face of the cover member, opposed to the plug, is formed integral with the protruding portion partially disposed within the axial opening end.

A shaft for transmitting torques includes a hollow shaft made of fiber-reinforced plastic. A flange which can be used to connect the hollow shaft to a driving or driven machine part is fastened at least to one end of the hollow shaft. The flange is fastened to the hollow shaft via a number of screw connections. Each screw connection includes a screw and a nut. The shank of the screw projects in the direction of the hollow shaft through an opening in the flange that is arranged in the connection region between the end edge of the hollow shaft and the flange. The shank extends at least partially inside the shell of the hollow shaft and engages with the nut arranged on the hollow shaft. The head of the screw is supported on that side of the flange opposed to the hollow shaft.

A phase varying apparatus capable of smoothly varying the phase angle of a camshaft relative to a drive rotor by comprising: a drive rotor supported by a camshaft and driven by a crankshaft; a first control rotor integral with the camshaft; a first torquing mechanism for providing the first drive rotor with a torque in one direction, and a reverse rotation mechanism for proving the first control rotor with a torque in the opposite direction, wherein the reverse rotation mechanism comprises a first radius-decreasing guide groove formed in the control rotor, a crank member adapted to rotate about a position offset from the rotational axis of the drive rotor, and a first pin mechanism mounted on the crank member and movable in the radius-decreasing guide groove, and a second operative mechanism for rotating the first control rotor in the opposite rotational direction relative to the drive rotor.

A propshaft assembly that includes a tubular member, first and second end connections coupled to opposite ends of the tubular member and a damper that is received in the tubular member and positioned between the first and second end connections. The tubular member has a wall member that defines an interior circumferential surface. The damper has a first damping device, a second damping device and a third damping device. The first damping device has a first core and a first damping member that is fixed to the first core. The first damping member extends helically about the first core and engages the interior circumferential surface. The second damping device is formed of foam and is positioned in the tubular member between the first and third damping devices. The second damping device engages the interior circumferential surface. The third damping device has a second core and a second damping member that is fixed to the second core. The second damping member extends helically about the second core and engages the interior circumferential surface.

An electro-mechanical energy conversion device is provided having an armature with a central cavity. The armature is rotatably mounted in a frame. A torsion bar is positioned within the armature with one end connected to the armature and the other end connected with an energy source or consuming device.

A ball-detent torque-limiting assembly has breakout means for maintaining an axial separation distance between opposing pocketed surfaces of the assembly once the primary balls of the assembly have rolled out of their pockets, wherein the axial separation distance maintained by the breakout means is at least as great as the diameter of the balls. The breakout means may include a plurality of secondary balls deployed in a breakout event. The breakout means assumes the axially directed spring load that urges the opposing pocketed surfaces together, thereby preventing the primary balls from entering and exiting the pockets in quick and violent succession following breakout and avoiding damage to the torque-limiting assembly. The torque-limiting assembly is resettable by counter-rotation following a breakout event.

An arrangement transmits a torque between a shaft and a hub. The hub has at least approximately the interior geometry of an equilateral n-sided polygon, the side surfaces of which at least approximately bear against a clutch portion, which is of circular overall cross section, of the shaft, and wherein the shaft has at least one driver portion which is rotationally conjoint with respect to the clutch portion and which extends in the direction of a corner of the n-sided polygon.

A torsional vibration damping device is configured to have hysteresis torques in the positive and negative sides varied by a simple construction, thereby improving the efficiency of production work and preventing an increase in production cost. Friction materials are respectively provided on surfaces of a hub member and the disc plates, the surfaces facing each other in the radial direction when the hub member is twisted in the positive side with respect to the disc plates. The friction materials are to be brought into friction contact with each other when the hub member is twisted by a specific angle with respect to the disc plates.

A system and methods are provided for controlling a motor of a rod pumping system using previous RPMs of the motor and predicting an RPM of the motor; correcting a power factor of a motor of a rod pumping system; allocating energy consumption and allocating energy generation for a set of wells connected to an electricity meter using an amount of energy generated by each well; and generating an alert if a set of data is beyond a threshold for the set of data.