Abstract: Noise and vibration of a helically-toothed-belt transmission device driven under heavy load or at a high-speed rotation, are reduced. A backlash “D” is selectively enlarged in a helically-toothed-belt transmission device that transmits drive force by meshing between a helically toothed belt and a helically toothed pulley. That is, a tooth helix angle “?” is set in a range of ?0.2?1?W·?/Pt?0.75, with “Pt” being a tooth pitch, “?” a tooth helix angle, and W the width of the belt. The backlash “D” between the helically toothed belt and the helically toothed pulley is set to be 1.6%-3% of the tooth pitch “Pt”.

Abstract: An electric power steering apparatus includes a reduction gear mechanism (17) for reducing the rotation speed of an output shaft (16) of an electric motor (15). The reduction gear mechanism (17) comprises an inscribed gear (39) rotatable interlockingly with the output shaft (16), and a circumscribed gear (40) in which the inscribed gear (39) is inscribed. An endless belt connects a driving pulley (41) integrally rotatable with the circumscribed gear (40) and a driven pulley (42) disposed so as to surround a steerable shaft. By heightening the reduction gear ratio by the speed reduction using the inscribed gear (39) and the circumscribed gear (40), the reduction gear mechanism (17) as a whole can achieve a high reduction gear ratio without making the diameter of the driving pulley (41) very small.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

Abstract: An electric power steering apparatus comprises an electric motor for producing a steering assist force, and a speed reduction mechanism for decelerating the rotation of an output shaft in the electric motor. The speed reduction mechanism comprises an input pulley driven by the electric motor, an output pulley connected to a steering shaft, and a belt for connecting the input pulley and the output pulley to each other. The belt comprises a helical toothed belt. The input pulley and the output pulley respectively include helical toothed pulleys meshed with the helical toothed belt.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

Abstract: Noise and vibration of a helically-toothed-belt transmission device driven under heavy load or at a high-speed rotation, are reduced. A backlash “D” is selectively enlarged in a helically-toothed-belt transmission device that transmits drive force by meshing between a helically toothed belt and a helically toothed pulley. That is, a tooth helix angle “?” is set in a range of ?0.2?1?W·?/Pt?0.75, with “Pt” being a tooth pitch, “?” a tooth helix angle, and W the width of the belt. The backlash “D” between the helically toothed belt and the helically toothed pulley is set to be 1.6%-3% of the tooth pitch “Pt”.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other and a belt tension adjuster.

Abstract: An electric power steering apparatus includes a reduction gear mechanism (17) for reducing the rotation speed of an output shaft (16) of an electric motor (15). The reduction gear mechanism (17) comprises an inscribed gear (39) rotatable interlockingly with the output shaft (16), and a circumscribed gear (40) in which the inscribed gear (39) is inscribed. An endless belt connects a driving pulley (41) integrally rotatable with the circumscribed gear (40) and a driven pulley (42) disposed so as to surround a steerable shaft. By heightening the reduction gear ratio by the speed reduction using the inscribed gear (39) and the circumscribed gear (40), the reduction gear mechanism (17) as a whole can achieve a high reduction gear ratio without making the diameter of the driving pulley (41) very small.

Abstract: An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

Abstract: An electric power steering apparatus comprises an electric motor for producing a steering assist force, and a speed reduction mechanism for decelerating the rotation of an output shaft in the electric motor. The speed reduction mechanism comprises an input pulley driven by the electric motor, an output pulley connected to a steering shaft, and a belt for connecting the input pulley and the output pulley to each other. The belt comprises a helical toothed belt. The input pulley and the output pulley respectively include helical toothed pulleys meshed with the helical toothed belt.

Abstract: An electric power steering apparatus comprises a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism comprises an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and means for adjusting the tension of the belt.