Abstract: An object of the present invention is to provide a sprocket that mitigates the impact of tension fluctuations resulting from load torque changes, suppresses noise and vibration, ensures stable chain behavior, prevents sprocket durability loss and the generation of harmonics during rotation, along with a chain drive system. Tooth roots between adjacent teeth of the sprocket include those with a radial deviation from a root circle of a standard tooth profile, set within a predetermined numerical range corresponding to a tooth pitch. A phase variation pattern is created by changing a root radius in accordance with an angular position. The phase variation pattern has a waveform with an amplitude varied within a range of ( 1/7)Amax, where Amax represents a maximum amplitude. The chain drive system includes a plurality of sprockets and a chain passed over the sprockets, at least one of them being the above-described sprocket.

Abstract: To provide a sprocket that not only reduces impact and hitting noise caused by contact and seating of a chain when it meshes with the sprocket, but also simplifies a setting of process conditions for securing a cushion ring on a side face of a sprocket body. The sprocket includes the sprocket body formed with a plurality of teeth on a circumferential surface thereof, and the cushion ring provided to at least one side face of the sprocket body and having an outer circumferential surface that makes contact with link plates of a chain. The cushion ring is secured to the sprocket body without an adhesive layer.

Abstract: The present invention provides a toothed belt transmission that reduces noise and vibration resulting from the engagement between a toothed belt and a toothed pulley, and that improves the durability of the toothed belt. The toothed belt transmission in which a tooth height of a toothed belt and a tooth height of a toothed pulley are set so that when the toothed belt and the toothed pulley start engaging with each other, tooth tip parts of the toothed belt and tooth bottom parts of the toothed pulley contact each other before tooth bottom parts of the toothed belt and tooth tip parts of the toothed pulley contact each other.

Abstract: An object of the present invention is to provide a sprocket that reduces impact and knocking sound of contact or seating when meshing with a chain, and that improves the durability of an entire chain drive system by reducing vibration and noise. The sprocket includes a cushion ring having an outer circumferential surface that is configured to come into contact with link plates of the chain. The cushion ring includes a circumferential groove extending in a circumferential direction on the outer circumferential surface, and the circumferential groove has a width smaller than that of the link plates.

Abstract: The present invention provides a toothed belt transmission that reduces noise and vibration resulting from the engagement between a toothed belt and a toothed pulley, and that improves the durability of the toothed belt. The toothed belt transmission in which a tooth height of a toothed belt and a tooth height of a toothed pulley are set so that when the toothed belt and the toothed pulley start engaging with each other, tooth tip parts of the toothed belt and tooth bottom parts of the toothed pulley contact each other before tooth bottom parts of the toothed belt and tooth tip parts of the toothed pulley contact each other.

Abstract: A toothed belt is provided that has excellent environment resistance, high load resistance, high stiffness, and achieves high accuracy, light weight, compactness and low noise. A toothed belt is provided with a belt body including a plurality of core wires juxtaposed in the width direction of a rubber portion, a plurality of tooth rubber portions formed on one surface of the belt body, and a tooth cloth covering the surface of the tooth rubber portions. The rubber portion contains dioctyl sebacate and trimellitic acid ester in a mass part ratio of 1:19 to 1:1, the mass percentage of the dioctyl sebacate to the whole quantity of the rubber portion is less than 4 mass %, and the mass percentage of the total quantity of the dioctyl sebacate and the trimellitic acid ester to the whole quantity of the rubber portion is in a range from 4 mass % to 8 mass %.

Abstract: A toothed belt is provided that has excellent environment resistance, high load resistance, high stiffness, and achieves high accuracy, light weight, compactness and low noise. A toothed belt is provided with a belt body including a plurality of core wires juxtaposed in the width direction of a rubber portion, a plurality of tooth rubber portions formed on one surface of the belt body, and a tooth cloth covering the surface of the tooth rubber portions. The rubber portion contains dioctyl sebacate and trimellitic acid ester in a mass part ratio of 1:19 to 1:1, the mass percentage of the dioctyl sebacate to the whole quantity of the rubber portion is less than 4 mass %, and the mass percentage of the total quantity of the dioctyl sebacate and the trimellitic acid ester to the whole quantity of the rubber portion is in a range from 4 mass % to 8 mass %.

Abstract: A power transmitting toothed belt having improved positioning accuracy between the toothed belt and a pulley, increased durability, and reduced contact noise, comprising a rubber back layer, a plurality of core wires and a rubber layer having a plurality of belt teeth, wherein the belt teeth are at oblique angle with respect to the direction of the width of the belt. The belt teeth intersect with straight pulley teeth having a pitch equal to the pitch of the belt teeth.