Abstract: To provide a chain having a mechanism for preventing backbend which does not cause any reduction in power transmission efficiency when the chain is operating, which can suppress string vibration in the chain spans, and which is highly durable. A mechanism for preventing backbend is provided, in the chain length direction, with a plurality of spring washer structures (5) consisting of a pair of left-right spring washer parts (50, 51) which have linking pins (3) inserted therein, and linking bars (55) for linking the areas between the spring washer parts (50, 51); and adjacent spring washer structures (5) in the chain length direction extend in the length direction of the chain in a state in which the spring washer parts (50, 51) of each are overlapping. When link plates (2) undergo backbend, the spring washer structures (5) flex together with the link plates (2), and the mutual rotation of the spring washer parts (50, 51) causes an increase in the thickness of the spring washer structures (5).

Abstract: A link plate for silent chains includes a pair of teeth, each formed of an inside flank and an outside flank and a pair of pin apertures. A moment of force around a pin M=F×Lo, where F is a force applied by a sprocket tooth against the outside flank, and Lo is a length of a perpendicular drawn from a center O of a pin aperture to an action line of the force, is decreased by decreasing Lo. The link plate engages a sprocket tooth on an intersection between a straight line n and a flank, line n and the direction of a central line connecting each O forming a pressure angle ?, and contacting a circle having a center O and a radius r<0.25×P, where P is a pin aperture pitch. Also, ? of the outside flank satisfies an inequality, 32°??<34°, to lessen the force.

Abstract: A silent chain for restraining chordal action and improving noise and oscillation performance comprising a plurality of link plates each having a pair of teeth and pin apertures interlaced in link thickness and length directions and pivotably connected by connecting pins inserted in the pin apertures. Each of the teeth are formed of an inside flank and an outside flank. The inside flank of a first link plate projects from the outside flank of a second link plate whose one tooth overlaps a tooth of the first link plate when the chain is pulled straight. The inside flank and the outside flank are formed in such a way that 0.021*P≦&dgr;max≦0.063*p is satisfied where P is a chain pitch and &dgr;max is a maximum projection of the inside flank of the first link plate relative to the outside flank of the adjacent second link plate.

Abstract: A silent chain for preventing chordal action and conducting a smooth wrapping around a sprocket comprising a plurality of link plates that are arranged in lateral and longitudinal directions and pivotably connected by connecting pins. Each of the link plates has a pair of teeth and pin apertures into which the connecting pins are inserted. Each of the teeth are formed of an inside flank and an outside flank. The inside flank is formed of a first circular arc on the addendum side and a second circular arc on the dedendum side. Inequalities, R1≧2*P and R1>>R2, are satisfied where the radius of curvature of the first circular arc is R1, the radius of curvature of the second circular arc is R2, and the chain pitch is P.

Abstract: A link plate for silent chains 10 includes a pair of teeth or toes 10a each formed of an inside flank 11 and an outside flank 12 and a pair of pin apertures 10b to insert connecting pins 3 thereinto. A moment M around a pin 3 is shown as follows: M=F×Lo where F is a force applied by a tooth 21 of a sprocket 20 against a meshing point 12e on the outside flank 12, and Lo is a length of a perpendicular drawn from a center O of a pin aperture 10b to an action line m of the force F. In order to decrease this moment M, the length Lo of the perpendicular is shortened, said link plate having an engaging point E with a tooth of a sprocket on an intersection between a straight line n and a flank, said straight line n and the direction of a central line connecting each center O of pin apertures forming a pressure angle &agr;, and being in contact with a circle C, said circle C having a center located at a center O of said pin aperture and a radius r≦0.25×P, where P is a pin aperture pitch.

Abstract: In a silent chain, multiple link plates are interleaved and connected to each other by connecting pins in a rocker joint. The rocker joint includes a joint pin and a rocker pin which are inserted into pin apertures. Guide links are placed on both ends of the joint pins. The joint pins are slightly longer than the rocker pins. Each rocker pin and joint pin has a cross-sectional area. The cross-sectional area of the joint pin is made larger than that of the rocker pin. In another embodiment, the rocker joint has a joint pin with a greater thickness than that of the rocker pin. Another embodiment of the invention includes a rocker joint where the radius of the curvature of the rolling surface of the joint pin is greater than that of the rocker pin.

Abstract: A power transmission chain reduces the chordal motion, or up/down motion, of the chain, which permits a reduction in the noise of the chain. In the chain, the inside flank and outside flank of the link teeth are formed to satisfy P.sub.2 .gtoreq.P.sub.1 .gtoreq.P.sub.3 and R.gtoreq.2.times.P, when P.sub.1 is the pitch between the outside flanks on the mesh pitch line of link plates 2, P.sub.2 is the pitch between the inside flanks of two other adjacent link plates that engage with teeth of the links when the chain is stretched nearly straight, and P.sub.3 is the pitch between the inside flanks when the chain is wrapped around the sprocket. R is the radius of curvature of the inside flank and P is the chain pitch.

Abstract: A low noise chain drive of this invention includes toothed sprockets and an endless silent chain having sets of link plates successively connected for articulation by means of connecting members. Each set has a plurality of transversely aligned link plates with each having a pair of link plate teeth designed to engage the sprocket and a pair of openings through which the connecting members are inserted. The link plate teeth are defined by an outside flank and an inside flank. The sprocket has sprocket teeth defined by a sprocket tooth flank.The sprocket tooth flanks and the outside flanks are profiled such that the outside flanks have a swelling located between the tip of the link plate tooth and a point that is in contact with the sprocket tooth after the completion of the engagement.

Abstract: In a silent chain, guide link plates are installed in a row along the sides of the link plates. The guide link plates are provided with central openings having rounded corners. The width of the inner beam portion of the central opening is limited by the inner edge of the central opening and the inner edge of the guide link. The width of the outer beam portion of the central opening is limited by the outer edge of the opening and the outer edge of the guide link plate. The width of the inner beam portion is equal to or less than the width of the outer beam portion. Alternatively, the guide link plates are provided with slits extending from the inner edge, and the inner edges of said slits are curved.