TRANSMISSION DEVICE Russian patent published in 1998 - IPC

FIELD: mechanical engineering. SUBSTANCE: device has transmission mechanism with at least two transmission ratios, coupling facilities, facilities for reaction to torque in order to control coupling facilities, and facilities for taking up axial loads for axial displacement of toothed gear-wheels. Facilities reacting to torque are formed by two helical gears which are capable of joint sliding in axial direction. Transmission mechanism may be planetary. Epicyclic gear in it is coupled to input shaft, and carrier is coupled to output shaft. Sun gear is locked by free running coupling at moment when engagement is released. In this case, device operates as reduction gear. Sun gear rotates with epicyclic gear and with carriage when engagement is tight. Axial forces acting on sun gear and on epicyclic gear during operation as reduction gear, and created when use is made of helical gears, tend to compress springs through thrust bearing and to release engagement. Beginning with position of direct engagement, with some limit of torque overrun, engagement slips, as a result of which the above-indicated axial forces develop. They compress spring and accelerate engagement release. Device operates in reduction gear mode till input shaft torque decreases and allows springs to tighten engagement again. EFFECT: partial or complete automation of power transmission. 27 cl, 25 dwg