Abstract: A free floating tensioning device (10) for a conventional drive system that contains upper and lower stationary guide members (16) and (18) that are located on the outer edges of the upper and lower runs of the drive element (15) and bias the runs inwardly towards each other. The inwardly facing surfaces of the stationary guide member (16) and (18) are configured to form U-shaped channels (20) each with a bottom surface (22) and substantially vertical sidewalls (24). The guide members further includes two contact rollers (30) which are mounted within the U-shaped channels (20) to rollably engage the flexible drive element (15). Upper and lower spring clips (36) and (38) are secured to the outer surfaces of the stationary guide members (16) and (18).

Abstract: A belt handling system has a belt storage subassembly, a testing pulley subassembly, and a belt transfer subassembly. The testing pulley subassembly has first and second spaced, rotatable pulleys around which a belt to be treated can be trained. The belt transfer subassembly is operable to transfer a belt at the belt storage subassembly into an operative position trained around the first and second pulleys. The testing pulley subassembly has a belt removal unit which is repositionable between first and second positions. A belt trained around the first and second pulleys is movable from an engaged state with the first pulley wherein a belt trained around the first and second pulleys follows rotational movement of the first pulley and a disengaged state wherein the first pulley can be rotated without causing a belt trained around the first and second pulleys to follow rotational movement of the first pulley.

Abstract: A tensioning device for flexible drive elements such as chains or belts comprises a pair of opposing guide blocks and a connecting and tensioning assembly for spacing the guide blocks from each other. The guide blocks are slotted to receive the runs of the drive element. The assembly includes a pair of retainers which are connected together by rods and fasteners. Springs are positioned between each guide block and its respective retainer to bias the blocks toward each other. Each retainer is pivotally attached to its respective guide block to permit oscillating or pivoting movement while the drive element travels through the guide slots. The rods and fasteners permit adjustment of the spacing between the guide blocks to adjust the tension on the drive element.

Abstract: A ratchet tensioner comprising a ratchet (1) having a first ratchet prong (6) engageable with one of ratchet teeth (T) at a position displaced from the axis (O) of a ratchet shaft (3) toward the free end of a plunger (5), and a second ratchet prong (7) receivable between two adjacent ones of the ratchet teeth (T) at a position located on a line (N) extending through the axis (O) of the ratchet shaft (3) perpendicular to an axis of the plunger (5) when the first ratchet prong (6) is in mesh with the one ratchet tooth (T). A projecting length (S2) of the second prong (7), which is measured from the axis (O) of the ratchet shaft (3) to the top of the second ratchet prong (7) in a direction parallel to the perpendicular line (N), is made smaller than a corresponding projecting length (S1) of the first ratchet prong (6) at least by an amount equal to the given manufacturing tolerance in the production of the ratchet.

Abstract: A spring-assist drive for a pedal-operated rider-propelled vehicle such as a bicycle which makes use of a wind-up coil spring mounted within the frame of the bicycle as auxiliary power. The spring is selectively wound by the rider operating the pedals to turn a spindle on which is mounted a sprocket wheel. A chain from the sprocket wheel drives a pivoting gear assembly comprising a ratcheting sprocket and attached drive gear. In a preferred embodiment, the tension on the chain will be adjustable by a chain tension adjustment mechanism. The drive gear releasably engages a power gear mounted on a common hub with the spring. A brake band and drum assembly holds the energy in the spring until the brake is released by the rider, whereupon the spring unwinds to drive a sprocket wheel mounted on the common hub, which sprocket wheel is connected to a sprocket wheel mounted on the spindle, turning the rear wheel drive sprocket wheel and the rear wheel.

Abstract: A motor mounting apparatus supports a motor relative to a base for relative rotation about a pivot axis to control tension in an endless loop driving element. A driving element emcompasses a drive member driven by the motor about a drive member axis and a driven member coupled to a load and driven by the driving member about a driven member axis to transmit power from the motor to the load. The apparatus includes a threaded shaft rotatable by a user about a shaft axis. The shaft axis is fixed relative to a first of the base and motor. A rider is carried by the threaded shaft so that rotation of the threaded shaft about the shaft axis produces longitudinal translation of the rider along the shaft axis relative to such first one of the base and motor. A rigid link has a first end pivotally coupled to the rider and a second end pivotally coupled to a second one of the base and motor.

Abstract: A tensioner for traction elements such as belts and chains comprises a tension lever (2) on which is arranged a tension roller (3) for the traction element. A mounting lug (5) of the tension lever (2) is pivoted by a radial bearing (13) on an axle (6) provided on an engine block (4), while axial stops (8) are arranged on both ends of the mounting lug (5). The tensioner further comprises a tension spring element (1) which acts at one end on the tension lever (2) and at a second end on the engine block. To prevent rattling noises which result from axial displacements of the tension lever (2), the invention provides the arrangement of sealing rings (12) on the two axial ends of the mounting lug (5), which sealing rings (12) seal the radial bearing (13) at its front ends while projecting axially beyond the end surfaces of the mounting lug (5), the axial distance between the axial stops (8) being larger than the axial distance between the end surfaces of the sealing rings (12).

Abstract: A hydraulic autotensioner unit having an actuator which can be assembled easily and which can use a spring having a large coil diameter and thus a large spring constant. The autotensioner includes a pivotable arm and a tension pulley rotatably supported on the arm. The actuator is coupled to the arm to press the tension pulley against a belt. The actuator has a cylinder, a rod inserted in the cylinder, and a hydraulic damper mechanism mounted in the cylinder to damp the pushing force applied to the rod when it is pushed into the cylinder. The spring is provided around the cylinder, so that its size is not limited by a housing. A spring seat is fixed to one end of the rod by a pin. The spring seat is coupled to an engine block by a coupling piece. The spring and the spring seat can be mounted after mounting the hydraulic damper within the cylinder, so that the actuator can be assembled easily.

Abstract: To provide a belt-drive mechanism wherein the tension degradation of the circular belt and slips of the dviving pulley are prevented, and a precise tension adjustment of the circular belt is enabled aw well, a belt-drive mechanism, having a fixed pulley (24), an adjust pulley (26), a circular belt (25), and an adjustment assembly (41) for adjusting distance between the fixed pulley (24) and the adjust pulley (26) by shifting position of the adjust pulley (26), comprises a pair of fastening members (32) for fixing the distance after the distance is adjusted. The adjustment assembly (41) comprises: a coupling member (31) having a screw hole (30); a pair of elastic members (32) for tensioning the shaft (27) outward of the circular belt (25); and an adjusting screw (29) set through a hole of another supporting face (28) to be screwed into the screw hole (30) of the coupling member.

Abstract: An oil skimmer of the endless belt type which is transportable as a unit is disclosed. The unit has an adjustment for adjusting the location of the axis of head pulley rotation and a floating tail pulley to assure accurate tracking of the belts on the pulleys and consistent and appropriate tension on the belt. The tail pulley features L-shaped spokes having legs that provide limited pulley-to-belt contact, minimizing oil transfer from the belt to the tail pulley, and also providing a mechanism for forcing oil against a descending belt reach to provide enhanced oil pick-up.

Abstract: A tensioner for belts and chains having a housing (1) in which a cylinder (3) containing a slidably guided piston (4) is arranged which piston (4) is supported radially by a guide bush (5), one end of a compression spring (13) engaging the piston (4), while the other end thereof engaging a cylinder base (6) of the cylinder (3), which cylinder base (6) is axially supported on a housing bottom (9) by a self-adjusting bearing (10) whereby, to improve the correction of alignment errors between the cylinder (3) and the piston (4), a plurality of peripherally adjacent raised portions (10) made of a ductile material are arranged between the housing bottom (9) and the cylinder base (6) and are plastically deformable under loading by the spring-loaded cylinder base (6).

Abstract: A belt tensioner of the Zed type with a base member, a pivot-arm, a pivot-pin, a pulley attached to the pivot-arm, a torsional spring attached between the base member and pivot-arm, and wherein the base member has a "tube pan" shape with a cantilevered inner wall that supports the pivot-pin, a cantilevered outer wall, and a bottom wall interconnecting the inner and outer walls and oriented with the bottom wall juxtaposed the pivot-arm. Optionally, the spring is connected to a damping mechanism that generates a reaction force in generally the same direction as a belt force or hub load. In another embodiment, a second, damping spring generates a reaction force in generally the same direction as the belt force with a constant damping force.

Abstract: A belt drive arrangement has a drive belt 14 which passes around and transfers rotation between a plurality of ratable members (pulleys) 16, 26, 20, 22, 24. The drive belt path includes both a belt tensioner 18 and an idler pulley 22. The idler pulley has a rotation axis and is mounted to a fixed structure on a mounting axis 36 which is eccentric to the rotation axis. The idler pulley is provided with a lever 40 by which it can be rotated about the mounting axis to vary the position of the surface of the idler pulley which is in contact with the belt relative to the mounting axis, and thus to vary the tension in the belt.

Abstract: In a mechanical chain tensioner (K) which comprises a molded part having fastening openings and abutments, as a basic body (G) on which a tension bracket (B) can be mounted on the abutments, the basic body (G) is an integral molded part of filled or reinforced, injection-moldable plastic.

Abstract: A hydraulic tensioner having an air vent channel formed within or on its housing is provided. Air that mixes into the fluid chamber discharges from the fluid chamber in the bore to an external attachment surface of the housing. The air vent has a circuitous path from the inner wall surface to the external attachment surface, wherein the air vent has cross-sectional area substantially less than the cross-sectional area for the passage to the fluid chamber.

Abstract: An apparatus for use with motor-driven assemblies is described. The motor-driven assembly comprises a motor, a pulley driven by the motor, a driven element and a belt drive connecting the pulley and the driven element. The apparatus comprises a motor base and a pivot base. The motor is arranged on the motor base such that, due to the positioning of its mass, the motor will pivot away from the drive element. However, pivoting in this direction is opposed by the belt drive. Thus, as the belt drive tension reduces, the motor will pivot away from the drive element, thereby tightening the belt. A one-way restraining means connecting the pivot base and the motor base prevents the motor from pivoting back toward the drive element, thereby keeping the belt drive taut and retaining drive design expectations.

Abstract: A ratchet type tensioner with a buffer mechanism is capable of buffering an impact force applied from a chain side to a plunger, irrespective of the amount of backlash in a ratchet mechanism, and is capable of exhibiting an excellent effect of suppressing vibration of the chain. An inner plunger is inserted in a protrudable and retractable manner into an outer plunger whose backward movement is restricted by a ratchet mechanism. The inner plunger is urged in its protruding direction by means of an inner plunger spring more powerful than a plunger spring which urges the outer plunger in the protruding direction. At one end of inner plunger is an oil storage chamber in communication with a high pressure chamber at the opposite end of the inner plunger through a check valve. A clearance path is provided between the two chambers to allow oil in the high pressure chamber to bypass the check valve and flow through the clearance path.

Abstract: A tensioning system for an endless chain comprising a snail cam mounted on a second shaft parallel to a sprocket shaft which supports a sprocket and chain, a follower running against the snail cam and mounted on a mechanism supporting the sprocket shaft, a ratchet device which selectively limits the rotational direction of the second shaft so that the radius of the snail cam at the follower increases with rotation, a means of applying a controlled rotational force to the second shaft to advance the ratchet device if chain tension is below a predetermined level, but not advance it if chain tension is above a predetermined level.

Abstract: A chain adjuster for bicycles includes a body having one of two sides thereof a dovetail groove and a hole defined laterally therethrough for an axle of rear hub extending therethrough, a tubular member extending laterally therefrom, a first block slidably received in the dovetail groove, a second block fixedly connected to one of two ends of the body and an adjusting bolt threadedly extending through the second block to contact the first block. The first block is pushed by the adjusting bolt to push the bicycle's rear fork tip so as to adjust a tension of the chain.

Abstract: A chain tensioner including a housing having a cylinder chamber, a rod member in the form of a threaded shaft inserted in the cylinder chamber for tensioning a chain, a tension adjusting spring for biasing the rod member outwardly of the housing, a hydraulic damper for damping axial dynamic load applied to the rod member from the chain by utilizing as a damping medium a hydraulic oil supplied into a closed end of the cylinder chamber through an oil supply passage formed in the housing and a check valve, and a thread engagement arrangement for preventing the rod member from retracting under an axial static load applied to the rod member. The chain tensioner can prevent the entry of air in the pressure chamber of the hydraulic damper when the engine is started in a cold environment or restarted.

Abstract: An accessory belt tensioner of an automotive engine includes a hub adapted to be fixed to an engine, an arm journaled upon the hub, a tensioner pulley mounted upon the arm, and a torsion spring interposed between the arm and hub. An antirotation lock incorporated within the arm and pulley locks the arm to the hub whenever the rotational speed of the pulley exceeds a predetermined threshold.

Abstract: A tensioner device for a power transmission chain, which has a small number of components and hence is able to reduce the cost of manufacture and assembly, can be mounted or installed easily, and requires only a small space for installation thereof. The tensioner device consists of a tensioner lever (4) pivoted at one end thereof on a support shaft (3) disposed on a fixed member (2) and carries, on a surface thereof facing a chain (7), a shoe (8) slidably engageable with the chain (7). The opposite end of the tensioner lever (4) has formed therein a plunger receiving hole (9) having an opening (9A) facing in a direction opposite to the surface to which the shoe (8) is attached. A plunger (10) is slidably received in the plunger receiving hole (9) and is held in abutment with a stopper (17) disposed on the fixed member (2).

Abstract: A hydraulic tensioner having an internal rack mechanism is provided. The tensioner has an engagement aperture formed within the sleeve of the bore, a pin member attached to the piston that engages the engagement aperture, and an elastic member between the sleeve and bore.

Abstract: The tensioner arms or guides of the present invention are constructed of two or more laminations with a plastic guide portion. These laminations replace the typical die cast aluminum or injection molded plastic bracket.

Abstract: The present invention relates to a semiconductor fabricating apparatus having an electrical system for transmitting a rotatory power through a belt of a motor to a pulley. The semiconductor fabricating apparatus having an electrical system of the present invention includes a sensor disposed in the vicinity of the belt for detecting a distance between the sensor and the belt and generating an electrical signal corresponding to a detected distance; an amplifier for amplifying the electrical signal to generate an amplified voltage; an analog-to-digital converter for converting the amplified voltage into a digital signal; and a controller for comparing the digital signal with a reference signal and determining whether the belt is loose on the pulley so as to generate a control signal.

Abstract: A tensioner for a power transmission belt and a method of making same are provided. The tensioner includes an arm that carries a belt engaging unit and is adapted to be pivotably mounted to a support unit. A mechanical first spring is operatively associated with the support unit and the arm for urging the arm, and hence the belt engaging unit, relative to the support unit and against the belt for tensioning same. A fluidic dampener is operatively associated with the support unit and the arm to dampen movement of the arm relative to the support unit. The dampener comprises a first plate fixed to the support unit, a second plate fixed to the arm for rotation therewith and relative to the first plate, a second spring urging the first and second plates against one another, friction material disposed between part of the facing surfaces of the first and second plates, and fluid disposed between the facing surfaces of the first and second plates.

Abstract: The present invention relates to a drive assembly having an endless rotating drive element which runs over a driving gear of a motor and a driven gear of a machine and a tensioning device for the drive element. The motor is arranged on a support which is supported in a positionally variable manner on a frame that carries the machine, and which is pretensioned vertically downwards by both the weight (G) of the motor and a pretensioning force (F) of a pretensioning unit which acts substantially in parallel with the weight (G) of the motor.

Abstract: A chain tensioner comprising an integrated tensioner body and tensioner arm. The tensioner body includes a fluid reservoir and a tensioner bore. The tensioner arm includes a pivot bore with a pivot pin disposed in the pivot bore to pivotally mount the tensioner arm. A check valve connecting the fluid reservoir to the tensioner bore permits fluid to flow into the tensioner bore, but not into the fluid reservoir. A plunger is slidably fitted into the tensioner bore and biased out from the tensioner bore by the fluid pressure in the tensioner bore. As a result, the plunger is forced against a fixed boss, causing rotational movement of the tensioner body and tensioner arm.

Abstract: To improve tracking, an exercise treadmill is provided with a frame including molded plastic pulleys, having an integral gear belt sprocket, an endless belt extending around the pulleys and a motor operatively connected to the rear pulley to drive the belt. The pulleys are molded out of plastic and have a diameter of approximately nine inches. A mold and method for producing large diameter treadmill pulleys having an integrally molded sprocket are also disclosed. A deck underneath the running surface of the belt is supported by resilient members. A positive lateral belt tracking mechanism is used to correct the lateral position of the belt. A belt position sensor mechanism is used in combination with a front pulley pivoting mechanism to maintain the belt in the desired lateral position on the pulleys. The exercise treadmill also includes a lift mechanism with an internally threaded sleeve engaged to vertically aligned nonrotating screws. A user display of foot impact force on the belt is also provided.

Abstract: A tensioning eye for use in a tensioner for a traction drive, in particular a belt drive, in an internal combustion engine, includes a fastening sleeve, a bushing, and an elastic ring circumscribing the bushing for securing the bushing in a bore of the fastening sleeve. The elastic ring has opposite ends formed with radially outwardly directed flanges which are spaced from opposing end faces of the fastening sleeve and define an outer diameter which is greater than a greatest inner diameter of the recess so as to form a radial overlap.

Abstract: A hydraulic tensioner having a hollow plunger slidably fitted in a cavity in a housing and biased in a protruding direction by a spring and fluid. A check valve permits fluid to only flow into the cavity, and thereby protrude the plunger, but not out of the cavity. A sleeve slidably fits within the plunger hollow forming a small clearance between the lower end of the plunger and sleeve. The plunger is made of an elastic material capable of expanding in diameter upon increases in internal pressure to permit increased fluid flow through the increased clearance and thus release cavity fluid pressure to allow the plunger to recede into the cavity.

Abstract: A tensioner arm and a chain guide are constructed with an oil-escape portion, which is designed to allow for the drainage of oil that collects on the back side of the tensioner arm or chain guide. The oil escape portion is comprised of a through-hole on the back side of the tensioner arm or chain guide or through-holes in the side walls located on the back side of the tensioner arm or chain guide.

Abstract: A tensioner for a power transmission belt and a method of making same are provided. The tensioner includes an arm that carries a belt engaging unit and is adapted to be pivotably mounted to a support unit. A mechanical first spring is operatively associated with the support unit and the arm for urging the arm, and hence the belt engaging unit, relative to the support unit and against the belt for tensioning same. A fluidic dampener is operatively associated with the support unit and the arm to dampen movement of the arm relative to the support unit. The dampener comprises a first plate fixed to the support unit, a second plate fixed to the arm for rotation therewith and relative to the first plate, a second spring urging the first and second plates against one another, friction material disposed between part of the facing surfaces of the first and second plates, and fluid disposed between the facing surfaces of the first and second plates.

Abstract: A mechanical chain tensioner for automotive engine timing drives. This invention relates to a tensioner that must be packaged in a confined space and having limited access for installation. This tensioner with a shoe and spring is the last timing component to be installed and fastened to the engine using a shoulder bolt, and this is done after its support bracket, if used, and the timing chain and sprockets are already in place. In addition, the tensioner includes a retaining feature that assures the spring will remain within the shoe during shipping, installation, and use of the tensioner.

Abstract: An independently steerable drive pulley is operable by the means of a non-concentric adjustable steering bushing mounted interiorly of a bearing fitted within the bore of the pulley, with the steering bushing and bearing and pulley being mounted on a drive shaft, with a pin and roller assembly for transmitting torque from the drive shaft to the pulley, the steering bushing being adjustable for changing the angular alignment of the pulley with respect to the drive shaft upon which it is mounted, following which adjustment the steering bushing is locked upon the shaft.

Abstract: A tensioning device for a reciprocating flexible drive system, such as a wire rope is provided. The tensioning device provides a mechanism which effectively tensions the slack side of the wire rope while directly coupling the driven side of the wire rope to the load. The tensioning device slides within a housing to a first position where force from the driven side is applied directly to the load while the slack side is tensioned with a spring. When the wire rope is reversed, the tensioning device slides to a second position within the housing where force from the driven side is once again directly applied to the load.

Abstract: An auxiliary chain tension system for a rear derailleur in a bicycle, the auxiliary chain tension system being composed of: an elongated member having two opposed ends, one end being formed to secure the member in a fixed position relative to the rear wheel fork of the bicycle so that the other end extends rearwardly from the rear wheel fork, the other end of the elongated member being formed to retain; a spring retention member securable to a pulley shield of the derailleur; and a tension spring having a first end connectable to the other end of the elongated member and a second end connectable to the spring retention member for imposing an auxiliary tension force on the bicycle drive chain.

Abstract: A belt tensioner of the Zed type with a pivot-arm attached to an off-set cylindrical member supported by sleeve-type bushings with axially spaced-apart bearing surfaces disposed over a pivot where the bearing surfaces have an axial length that is sized for an average pressure contact. The tensioner may include a spring activated damping mechanism with a brake shoe having oppositely facing inside ramp surfaces which operate in such a manner to provide a normal force that is greater than a spring force applied to the brake shoe.

Abstract: An image forming apparatus includes an image former for forming an image on an image carrier, a conveyor belt for conveying an image receiving medium to the image carrier, a conveyor roller structure having a first roller with different diameter at both ends and taper size T expressed by T=(D-d)/L, wherein D is the diameter at the large diameter side, d is the diameter at the small diameter side and L is the length of the first roller, which is more than 2.341.times.10.sup.-3 and a coefficient of static friction is less than 0.26. A second roller is provided opposite to the first roller, for moving the conveyor belt in a prescribed direction by rotating the first and the second rollers in a state where the conveyor belt is put over the first and the second rollers, and a transferring structure for transferring the image formed on the image carrier onto the image receiving medium.

Abstract: A measuring and control device for guiding a steel belt along a longitudinal axis of a continuously operating press includes a driving drum and a reversing drum for guiding the steel belt. Two measuring columns are respectively anchored in a foundation and spaced longitudinally from either longitudinal side of one end face of the continuously operating press. Four path sensors are disposed on the measuring columns, such that each of the path sensors measure a spacing between the sensor and a point on the continuously operating press. Pressure cylinder-piston arrangements are disposed on the driving drum and the reversing drum to correct the course of the steel belt. Variables for altering the course of said steel belt include the spacings measured by the path sensors.

Abstract: An automatic tensioning and damping element for endless chain drives includes an elastically deformable which automatic tensioning and damping element (3) exhibits a on its outer surface a guide profile matching the profile of the chain with a guide play and which automatic tensioning and damping element (3) is disposed pretensioned between the load strand (1) and the loose strand (2). The automatic tensioning and damping element (3) supports itself slidingly in the loose strand angle and is thus automatically controlling and self-adjusting in its distance relative to the chain wheels.

Abstract: An electrostatic copying machine including a drum that supports a photoreceptor belt. The drum includes a mechanism for reducing the drum perimeter, allowing a user to replace the photoreceptor belt.

Abstract: An apparatus is provided for adjustably mounting a prime mover in belt driving relation to a reciprocating compressor to facilitate proper tensioning, locating and aligning of a reciprocating compressor drive belt. The apparatus includes a base plate and a support plate which mounts the prime mover. A pivotal mounting means, which defines an axis of rotation, is connected to the support plate. At least one pair of locators are fixedly attached to the base plate. The at least one pair of locators removably receive the pivotal mounting means to adjustably locate the support plate with respect to the base plate. A pivotal adjustment assembly adjustably positions the support plate in a predetermined position along an arcuately shaped path of travel about the axis of rotation.

Abstract: An image forming apparatus includes a plurality of image carriers on each of which an image is formed, a conveyor belt for carrying an image receiving medium, a driving roller on which the conveyor belt is mounted for driving the conveyor belt to convey the image receiving medium and a pressing roller for pressing the conveyor belt against the driving roller. The images formed on the image carriers are transferred seguentially to the image receiving medium conveyed by the conveyor belt. A tensioning member causes the conveyor belt to skid to maintain proper relative positioning of the components.

Abstract: A drive apparatus that, together with securing the lateral symmetry of the overall apparatus, minimizes the number of parts while also achieving a smooth operating state. A rotating member is provided that makes sliding contact at its outside surface with opposing portions of a belt-shaped member wrapped around each rotor to obtain a parallel state with respect to said opposing members. Thus, a driving device in the form of a motor and so on that rotates and drives said rotors can be arranged on a line extending from the center in the direction of width of a driven object. As a result, the lateral symmetry of the overall apparatus is secured. In addition, since the number of parts can be minimized, together with achieving a reduction in costs, a smooth operating state is obtained since said rotating member only makes sliding contact with said belt-shaped member.

Abstract: An independently steerable idler pulley is operable by the means of a non-concentric adjustable inner sleeve bushing mounted interiorly of a radial ball bearing fitted within the ID of the pulley, with the sleeve bushing and bearing and pulley press fitted as an assembly for mounting on an idler shaft. The sleeve is movable in defining the angular alignment adjustment of the assembly with respect to the shaft upon which it is mounted. With the desired angular adjustment determined the sleeve is locked upon the shaft. Plural of such pulleys supported on a common shaft can be individually positioned.

Abstract: The invention effects an increase in the range of continuously variable tool speed and torque control for machine tools beyond that conventionally available for operation from single phase alternating current. Interactive operator control of mechanical speed regulation is additively coupled to electrical control of direct current motor drive to reduce or eliminate machine down time needed for performing a series of varied machine operations.

Abstract: A low noise active tracking pulley idler reduces noise and actively tracks belts entrained around it by storing up undesirable impact energy and using it to guide the belts positioned around it. The idler includes an idler that is an integral member and has two cylindrical end portions with a flexible middle portion between them.

Abstract: To improve tracking, an exercise treadmill is provided with a frame including molded plastic pulleys, having an integral gear belt sprocket, an endless belt extending around the pulleys and a motor operatively connected to the rear pulley to drive the belt. The pulleys are molded out of plastic and have a diameter of approximately nine inches. A mold and method for producing large diameter treadmill pulleys having an integrally molded sprocket are also disclosed. A deck underneath the running surface of the belt is supported by resilient members. A positive lateral belt tracking mechanism is used to correct the lateral position of the belt. A belt position sensor mechanism is used in combination with a front pulley pivoting mechanism to maintain the belt in the desired lateral position on the pulleys. The exercise treadmill also includes a lift mechanism with an internally threaded sleeve engaged to vertically aligned nonrotating screws. A user display of foot impact force on the belt is also provided.

Abstract: A power transmission system having: a power transmission belt with a tensile strength such that a force of at least 17 kgf per 1 mm width is required to effect a 1% elongation of the belt; a plurality of pulleys with which the power transmission belt is operatively engaged; and an auto-tensioner having an element to engage the power transmission belt. The auto-tensioner has a damping ratio that is not greater than 20%, where the damping ratio is defined by the following formula: Damping ratio=2[(A-B)/(A+B)].times.100, where A is the force exerted by the auto-tensioner element during up-stroking of the auto-tensioner element and B is the force exerted by the auto-tensioner element during down-stroking of the idler pulley. More preferably, the damping ratio is 10-20%.