摘要:
A toroidal-type continuously variable transmission includes three trunnions and power rollers in a single cavity. One of the trunnions is shifted by a pair of oil pressure actuators, each of a single-acting type. The remaining two trunnions are respectively shifted by separate oil pressure actuators, each of a double-acting type.
摘要:
In a toroidal-type continuously variable transmission, at least one of components including inner and outer races of a power roller bearing, an input disk, and an output disk is composed of an alloy steel material containing C: 0.15 to 0.5 wt %, Si: 0.1 to 1.5 wt %, Mn: 0.1 to 1.5 wt %, Cr: 0.5 to 3.0 wt %, and at least one kind selected from Mo: 0.1 to 3.0 wt % and V: 0.1 to 3.0 wt %, a content of 0 in the alloy steel material being set to be not more than 9 ppm; and the surface of the at least one component after carbonitriding, hardening and tempering treatments is set to contain C: 0.8 to 1.2 wt % and N: 0.05 to 0.20 wt %, and the at least one component has surface hardness of Hv 720 or more, and Mo.V carbide/carbonitride, the average particle size of which is in a range of from 50 nm to 500 nm is dispersed and precipitated on a race surface or in a range of from the race surface to a deep position where a maximum shearing stress is generated.
摘要:
The toroidal type continuously variable transmission includes: first and second disks concentrically disposed on each other and supported such that they can be rotated freely; a pair of trunnions; a pair of displacement shafts respectively including support shaft portions and pivot shaft portions; a plurality of power rollers interposed between and held by the first and second disks; a plurality of thrust ball bearings respectively for supporting their associated power rollers; and, a plurality of thrust needle bearings respectively interposed between the outer surfaces of outer rings respectively forming the thrust ball bearings and the inner surfaces of the trunnions. A retainer for retaining the thrust needle roller in a freely rollable manner is formed of a single plate, and is carbonitrided, while the surface hardness Hv of the retainer is set higher than or equal to 550.
摘要:
The disk has a traction surface having a concave-arc-shaped cross section which is interposed between a small diameter end portion and a large diameter end portion. In the central portion of the end face of the disk on the small diameter end portion side, there is formed a through hole which extends through the disk up to the large diameter end portion side end face of the disk, while the inner peripheral surface of the through hole is used as an inside diameter surface of the disk. Here, when, among metal flows existing in the disk, a metal flow, which has such a positional relationship with respect to the surface of the disk that an angle .theta. formed between a metal flow on the traction surface side and the tangent of the traction surface is smaller than or equal to 30 degrees, is defined as a "metal flow along the disk surface", the disk is structured such that the "metal flow along the disk surface" exists at least in the traction surface.
摘要:
The ball spline for use in a troidal-type continuously variable transmission comprises a plurality of spline grooves and a plurality of balls which are arranged in series within spline gaps each constituted by a set of mutually opposing spline grooves, in which, while allowing the movement of the input disc in the direction of an input shaft by means of contact between the spline gaps and balls, the input shaft and input disc can be drivingly connected to each other. In the ball spline, the number of spline gaps is set different from integral multiples of the number of power rollers which are held by and between the input and output discs in contact with the two discs in order to transmit a rotation torque between the input and output discs. Further, each of the spline grooves includes inner and outer peripheral surface side spline grooves, and the shape of each of the sections of the two inner and outer peripheral surface side spline grooves respectively forming the ball spline is formed as a Gothic arch shape. And, the radius of curvature of the section of the groove bottom portion arc surface forming the groove bottom portion of each of the spline grooves is set more than or equal to 15% of the diameter of the ball. Also, the outer peripheral surface side chamfers of the outer peripheral surface side spline groove are set smaller to thereby be able to secure the effective grinding surface of the outer peripheral surface side spline groove.
摘要:
A flow control device, responsive to the rotational speed of a pump and to load pressure, has a simple structure. And a housing of the flow control device for saving energy can make use of a general pump housing not for saving energy as a common housing.The flow control device of a power steering apparatus, arranged in a housing of a pump, includes a flow control valve and a load pressure responsive valve. The flow control valve includes a bypass spool with a control rod penetrating a metering orifice. The load pressure responsive valve is incorporated in a union for response to the load pressure. The control rod is located on the bypass spool for response to the rotational speed of the pump.
摘要:
In order to improve the transmission efficiency of a toroidal type continuously variable transmission by reducing the dynamic torque loss of an antifriction bearing, a first output gear is constituted by a pair of helical gears of which the directions of inclinations are opposite to each other, and a second output gear is constituted by a double helical gear. By this construction, a thrust force created in the meshing portion between the first and second output gears is offset and the dynamic torque loss of the antifriction bearing is reduced.
摘要:
In order to prevent strong bending stress given to outer rings of thrust ball bearings of power roller assemblies and to improve the durability of the outer rings, a toroidal-type continuously variable transmission has thrust needle bearings which absorb thrust load given to the outer rings as well as allow the outer rings and corresponding trunnions to be shifted from each other. Preferably, the entire circumference of the pitch circle of the balls of each thrust ball bearing overlaps with a load-absorbing region, which is one or more annular and/or arcuate regions having the same width as the needles of needle bearings radially arranged in said regions in order to absorb thrust load.
摘要:
Construction of a friction roller reducer is achieved wherein displacement of intermediate rollers due to the change in thickness in the axial direction of loading cam apparatuses can be performed smoothly, and excellent transmission efficiency can be obtained. Long guide holes that are long in the radial direction of a sun roller and ring-shaped roller are provided in guide blocks that are fastened to a support frame for supporting the end sections of rotation shafts of intermediate rollers. The outer rings of ball bearings, of which the inner rings are fitted around and fastened to the outside of the end sections of the rotation shafts, engage with the long guide holes so as to be able to displace in the radial direction of the sun roller and the ring-shaped roller.
摘要:
A sleeve 28 making up a gear ratio control valve 21 is driven by not only a stepping motor 29 but also a secondary actuator 47. Pressure oil is made free to be introduced into the secondary actuator 47 through a manual oil pressure switching valve 37 which is switched over by a gearshift. Then, when the gearshift is operated from a non-running state to a running state, a gear ratio of a toroidal type continuously variable transmission is corrected by a predetermined amount by driving the sleeve 28 by the secondary actuator 47. As a result, while improving characteristic of a vehicle when starting from rest, the vehicle can be prevented from being reduced in speed unintentionally excessively even when the gearshift is operated while running.