Abstract: A tension-adjusting device for a driving belt comprising a tension roller and having an engagement arrangement provided between a support of the tension roller and a machine frame for enabling stepwise swiveling movement about a partially disengaged mounting bolt. The axis of swivel is radially displaced from the rolling axis of the tension roller. The engagement arrangement comprises a projection formed on the support radially displaced from the axis of swivel and a plurality of depressions formed in the machine frame and arranged at regular intervals along an arc defined by the path of travel of the projection during swiveling, whereby the projection is engageable with each depression, thereby defining a corresponding step in a range of adjustment of the tension of the driving belt.

Abstract: An off the road motorcycle having a balloon tired rear wheel that is suspended by a trailing arm and which is driven by a pair of flexible transmitters, one positioned closer to the motorcycle center line than the other so as to provide clearance for the rider's feet. An arrangement is provided for adjusting the tension in each of the two chains and one of these adjusting mechanisms moves the pivot point of the trailing arm relative to the frame.

Abstract: The belt stretcher unit is designed for assembly on a drive provided with a flexible member, e.g. for motor vehicles and consists of a pin, pivoting round a first axis, and of a pulley turning on the pin round a second axis eccentric with the first; the pulley is supported on the pin by at least one rolling bearing, and between the pin and the bearing, provision is made for an annular element made of elastic material.

Abstract: A tensioner has rolling members disposed between a rotatable outer member and a fixed inner member. The inner member has a bottom wall at at least one end thereof. The bottom wall has therein an eccentric position aperture for position adjustment situated at a position deviated from the axis of the inner member. A fixing bolt extends through said aperture. A spring member having at least one end which can be restrained by the inner member and the other end which can be restrained by the restraining portion of a support member to which the tensioner is mounted is provided within the inner member. Thus, a desired tension may be imparted to a transmission strap contacting the outer member by the spring member.

Abstract: A motor speed changer for an electric motor wherein a mounting platform is mounted directly to the end face of an electric motor by means of special fasteners. The fasteners comprise cylinders having eccentric portions thereon which are rotatable and alignable with the ends of the through bolts of the electric motor by rotation of the cylindrical fastener. The mounting platform is provided with an integral bearing housing and bearing for rotatably housing a jackshaft. The jackshaft is connected to the output shaft of the motor by means of a two pulleys and a drive belt.

Abstract: A mechanism which maintains drive belt tension substantially constant when the drive belt is mounted on sheaves with a non-fixed center distance such as the sheaves and belt utilized in vibratory earth compaction equipment, shakers and the like where off-centered weights are rotated at high speeds to obtain desired vibrations. The mechanism includes a driven sheave that is mounted eccentrically on the rotating shaft which supports the off-center weight with the eccentricity of the eccentrically mounted sheave being in the same direction as the offset of the off-center weight. This arrangement allows the center distance between the drive sheave and driven sheave to remain relatively constant thus retaining the drive belt tension relatively constant.

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

Abstract: A tension roller with a supporting member, pivoted on a pivot stud against the force of a tension spring, and rotatably supported in a roller sleeve by a bearing. The supporting member has a cylindrical interior space, limited by side walls, containing the tension spring. The side walls have bores for the pivot studs and recesses for formation of the stopping faces, against which the free ends of the tension spring abut in order to limit the angle of rotation of the tension roller. The member is made of synthetic material, using injection molding techniques. In order to produce this supporting member in an economical manner, additional recesses permitting insertion of a forming tool consisting of two halves are provided in the side walls of the member.

Abstract: An automatic belt tensioner of the type including a pivoted arm and belt engaging pulley includes an improved tensioning means to maintain a constant tension on a drive belt. A cam having an eccentric portion is wrapped and stretched by an elastomer strap. As the strap stretches, the point of tangency of the wrapped strap varies continuously to vary the effective moment arm of the tensioned strap on the cam, which is rigid to the pivoted arm. The strap tension, and the effective moment arm given by the radius of the point of tangency, are matched at each point to give a constant torque and belt tension.

Abstract: A mechanical drive mechanism of the endless belt and pulley type having an improved belt tensioning arrangement. The shaft of the machine being driven (or that of the driving member itself) is eccentrically journaled with respect to its cylindrical bearing hub and a rigid arm having a first bore therethrough is disposed with the hub of the machine centered in that first bore. Located at the opposed end of the rigid arm is a parallel bore in which the other drive or driven shaft is journaled. Because of the eccentricity between the first shaft and its hub, as the arm is rotated about the hub as a center, the distance between the centers of the driving and driven shafts is increased or decreased, depending upon the direction of rotation of the rigid arm. As such, the tension of the endless belt coupling the drive and driven pulleys can be varied.

Abstract: A tension roller for enabling adjustment of the tightness of a driving belt, comprising a solid support and a bearing press-fit thereon. The solid support has an axially extending mounting bore eccentrically arranged therein and a seating surface formed circumferentially thereon. A plurality of balanced bores are circumferentially distributed in the support in order to obtain a uniform radial elasticity at the seating surface. The balance bores may have a diameter equal to or less than the diameter of the mounting bore. In the latter case, the shortest distance between the balance bore surfaces and the seating surface is equal to the shortest distance between the mounting bore surface and the seating surface. The resultant uniformity of the radial elasticity prevents deformation of the bearing.

Abstract: A device for maintaining a constant tension on an endless drive belt which supplies power to and drives the vehicle accessories. A mounting bracket is adapted to be mounted on an engine in a stationary position adjacent the drive belt and has an idler pulley rotatably mounted on an end of a lever. The lever is pivotally mounted on a shaft which extends outwardly from the mounting bracket. A torsional coil spring biases the idler pulley into tensioning engagement with the drive belt. The pulley is mounted on a stub shaft which extends parallel with the pivot shaft and is formed with an outer annular belt engaging surface. The pivot shaft is located within the periphery of the pulley belt engaging surface and the radial center line of said belt engaging surface intersects the bearing surface of the pivot shaft to provide a compact, low friction belt tensioner.

Abstract: A rear axle supporting structure in a three-wheeled motor vehicle equipped with a chain drive mechanism. A holder member having an eccentric bore is fitted in a pipe member which is fixed to the rear end of a swing arm, and a rear axle is inserted in the eccentric bore of the holder member. A brake caliper for braking a brake disc is connected to the holder member through a caliper supporting member concentrically rotatably with respect to the eccentric bore of the holder member.Adjustment of the drive chain is effected by turning the holder member, without affecting the positional relation between the vehicle body frame and the swing arm, without any inclination of the rear axle occurring, and while maintaining a constant positional relation between the brake disc and the brake caliper.

Abstract: In a wood circular sawing machine, a support for the circular saw which includes a rotary eccentric member mounted for rotation on a horizontal shaft which is in alignment with the axis of the output shaft of the motor, and a body which has its upper portion being mounted with the arbor of the circular saw and is provided with at its lower portion a hollow cylindrical member sleeved onto the eccentric member, wherein the body that supports the arbor can change the distance of the arbor from the axis of the output shaft of the motor by rotating the eccentric member.

Abstract: A tension roller for a drive belt is comprised of a two-part pin and a roller rotatably supported on the pin by a rolling bearing. One part of the pin is substantially solid and has a seating surface for receiving the inner ring of the rolling bearing. The other part of the pin is cup-shaped and extends over the seating surface to engage a side surface of the inner ring. An eccentric bore is provided in the pin for mounting the tension roller on a machine frame by means of a mounting screw. The eccentric bore, in the solid portion of the pin, extends to and separates the outer surface of the pin, whereby the mounting screw partially engages the inner ring of the bearing. The arrangement permits the maximum range of tension adjustments for the tension roller.

Abstract: Apparatus for maintaining substantially constant tension in an inelastic timing belt driven by a rigid, swinging arm, including a driven, circular pulley, an eccentrically mounted, circular idler pulley, an inelastic timing belt mounted about the driven and idler pulleys to provide minimum tension at mid-motion and maximum tension at the start and end of motion, and a rigid swinging arm pivotably mounted equidistant from the centers of the driven and idler pulleys and secured at one end to the timing belt.

Abstract: A belt tensioner comprises a shaft which is eccentrically mounted on a stud bolt so as to be rotatable thereon when a lock nut is loosened. A pulley is concentrically mounted on the shaft by means of a bearing and rotatable thereon. The shaft is urged by a spring in the direction to cause the pulley to move toward a drive belt. The shaft is fixed to a stationary member when the lock nut is tightened.

Abstract: A power transmission mechanism includes a gear member and an annular and eccentric floating member having internal gear teeth meshed with external gear teeth of the gear member. A pair of guide plates provided on both outer sides of either the gear member or floating member prevent lateral disengagement of the floating member from the gear member. A pair of seal rings arranged between the inner sides of the guide plates and the outer sides of either the floating member or gear member prevent entry of dust or the like foreign material into a substantially closed space between the teeth of the gear member and the floating member, to thereby improve the durability of the mechanism.

Abstract: An idler mechanism for maintaining tension on a drive belt in a drive belt system comprising an idler arm, a pulley mounted on the arm for rotation about a rotational axis, a pivotally adjustable mounting plate, means pivotally mounting the arm to the mounting plate eccentrically with respect to the pivot axis of the plate, and resilient means operatively associated with the pivotal mounting means for resiliently biasing the pulley into tensioning engagement with the drive belt. Application of a predetermined input torque to the pivot axis of the adjustable plate imparts a substantially constant tension to the drive belt substantially independent of belt length within predetermined tolerances.

Abstract: A tension roller pin including a hollow member, a rolling surface rotationally supported by a rolling bearing on said hollow member, an eccentrically displaced screw penetrating the pin for fastening the tension roller, a working surface for an adjusting member eccentrically displacing the pin by turning about the screw, the pin being formed as a continuous one piece hollow sleeve having a base at one end and a guide element at the other.

Abstract: A tension roller for belt drives comprises a pin designed as a hollow member and a roller member supported on the pin by way of a rolling bearing, with an inner ring, rolling means and an outer ring supporting the roller member. The pin is formed by two thin-walled sleeves positioned at opposite ends of the bore of the inner ring and the rolling bearing. At least one of the sleeves is provided on the surface thereof with a radial shoulder for emplacement of the inner ring.

Abstract: The casing of the electric generator of a motor vehicle is made of two cylindrical shells, one located eccentrically with respect to the other, connected together by struts to provide a light-weight rigid relation between the two belts. The casing is then mounted in a saddle-shaped support affixed on a mounting surface. Because of the eccentric position of the generator shaft within the outer cylindrical shell of the casing, loosening the tension band that holds the generator in place and rotating the casing of the generator makes possible tightening or loosening of the V-belt that drives the generator.

Abstract: As a counterbalance for an internal combustion engine a counterbalanceweight (7) driven by a crankshaft (2) of the engine by means of a non slipping drive is pivoted on a shaft (6) and combined with the driven part (8) of the non slipping drive. As a stretching or tensioning arrangement for the transmission means (9) of the non slipping drive, the shaft (6) supporting the counterbalanceweight (7) is provided with an eccentrically arranged journal pin (10) pivoted and lockable in the housing (1) of the engine.

Abstract: A wheeled vehicle is described having a drive sprocket bound onto the axle fixed to the vehicle and a driven wheel with a sprocket on its axle, with the driven chain connecting the sprocket for transmitting power from the drive sprocket to the driven sprocket. The invention comprises a chain tension adjusting device having a means for mounting the driven wheel axle for limited movement thereof toward and away from said drive sprocket axle, a fork frame having its legs rotatably mounted on the driven wheel axle on either side of the said driven sprocket and terminating at its closed end in at least one sleeve, with camming means mounted within said sleeve, and means for manually rotating said camming means within said sleeve so as to move said driven wheel axle by means of the fork frame toward and away from said drive sprocket axle.

Abstract: An improved chain speed reducer assembly comprising a drive shaft supported at one end by a first bearing block and by a second bearing block at the other end. Each of the bearing blocks has a shaft supporting bore that is axially displaced a predetermined offset distance from the central axis of the bearing block, and each of the bearing blocks is supported by a gear box frame so as to be selectively rotatable about the central axis of each bearing block. Attaching bolt connectors permit the bearing blocks to be secured at selected angular dispositions. This permits selective canting of the drive shaft, and when coupled with other similarly supported driven shafts supporting plural sprockets, separate strands of roller chains can be adjusted independently via the eccentric movement of the bearing block supporting bores upon selective rotation of the bearing blocks.

Abstract: A speed changing unit preferably for use on a model aircraft or powered foot-launched aircraft. A usual engine is mounted on a frame which in turn is adapted to be mounted on the frame of an aircraft. A pair of pulleys are mounted on the frame in a spaced relationship with a drive belt drivingly interconnecting the pulleys. One of the pulleys is mounted on the drive shaft of the engine for positive rotation with the drive shaft. The other pulley is rotatably mounted on a stationary eccentric shaft which is adjustably mounted on the frame. A propeller is mounted directly on this other pulley for rotation therewith when driven by the engine drive shaft and belt. Manual rotation of the eccentric shaft within its mounting adjusts the spacing between the spaced pulleys permitting different size drive shaft pulleys to be used with a standard drive belt to achieve different propeller speeds and thrust characteristics for a particular aircraft.