Abstract: Clearance Cs during a no-load stop and allowable value Cto of total clearance Ct obtained as a sum of clearance Ch occurring due to Hertzian stress are stipulated to a value less than height h of male coupling 28 along with an allowable value &sgr;hmo of the maximum Hertzian stress acting on rocking edge 26 being stipulated to a value less than an upper limit value &sgr;ho of the Hertzian stress that satisfies the opposing pitching lifespan. The radius of curvature R of the rocking edge is set within a range that satisfies R1≦R≦R2 for the radius of curvature R1 determined in correspondence with the allowable value &sgr;hmo of the maximum Hertzian stress and the radius of curvature R2 determined in correspondence with the allowable value Cto of the clearance between the total elements.

Abstract: In a belt for a continuously variable transmission including a large number of metal elements carried on metal ring assemblies each of which is comprised of a plurality of endless metal rings laminated one on another, the amplitude &sgr;a1 of a total stress on the inner circumferential surface of the innermost metal ring is larger than the amplitude &sgr;an of a total stress on the inner circumferential surfaces of the other metal rings, and a maximum value of a tensile stress on the inner circumferential surface of the innermost metal ring is larger than a maximum value of a tensile stress on the inner circumferential surfaces of the other metal rings. Therefore, a compressive residual stress is applied to the inner circumferential surface of the innermost metal ring used under the severest condition, and the middle value &sgr;m1 of the amplitude &sgr;a1 of the stress on the innermost metal ring is brought close or equal to 0.

Abstract: A shift control system comprises belt-speed calculation means, contact-circle enlarging pulley determination means, diameter-change calculation means, slip prevention thrust calculation means, speed ratio maintaining thrust calculation means and additional thrust calculation means. The diameter-change calculation means calculates the difference between the diameters of the contact circles at present and after a shift to a target speed change ratio, and the slip prevention thrust calculation means calculates a slip prevention thrust necessary for transmitting the power through a V belt without slip between the V belt and the drive and driven pulleys.

Abstract: When a tangential friction force received by a pulley abutment surface 37 of a metal element 32 from a pulley is represented by FV; a radial distance from a point 45 of action of the tangential friction force to a rocking edge 40 located radially outside the friction force-acting point 45 is represented by L; a radially inward load received by the metal element 32 from a metal ring assembly 31 is represented by FL; and a thickness of the metal element 32 is represented by t, the radial distance L and the thickness t of the metal element are determined, so that a relation, L/t≦FL/2FV is established. Thus, even if a moment FV×L is applied to the metal element 32 by the tangential friction force FV, the moment FV×L can be canceled by a moment FL×(t/2) generated by a load FL for urging an edge a of a ring slot 35 by the metal ring assembly 31, thereby preventing the inclination of the metal element 32 to enhance the durability of the metal ring assembly.

Abstract: A metal V-belt comprising an endless metal ring member 14 and a plurality of metal element members 10 supported along said metal ring member wherein the clearance between a slot portion S of the metal element members 10 and the endless metal ring member 14 is set larger than the clearance in the thickness direction of the belt between the concave and convex portions of a coupling portion 5 used for linking disposed on the front and rear surfaces of the metal element members 10. This controls damage to the metal ring member caused by contact between the metal ring member outermost periphery of the metal V-belt used in, for example, an infinite variable-speed drive and the metal element members.

Abstract: Clearance Cs during a no-load stop and allowable value Cto of total clearance Ct obtained as a sum of clearance Ch occurring due to Hertzian stress are stipulated to a value less than height h of male coupling 28 along with an allowable value &sgr;hmo of the maximum Hertzian stress acting on rocking edge 26 being stipulated to a value less than an upper limit value &sgr;ho of the Hertzian stress that satisfies the opposing pitching lifespan. The radius of curvature R of the rocking edge is set within a range that satisfies R1≦R≦R2 for the radius of curvature R1 determined in correspondence with the allowable value &sgr;hmo of the maximum Hertzian stress and the radius of curvature R2 determined in correspondence with the allowable value Cto of the clearance between the total elements.

Abstract: An endless metal belt (15) is formed by layering thin metal rings (30) in thicknesses to form tow layered ring structures (31) and fitting the two layered ring structures in slots (32a) formed in opposite side parts of each of metal blocks (32), extending on the opposite sides of a neck part (32e) of the metal block. The endless metal belt is extended between drive and driven pulleys (6, 11) respectively having variable effective diameters to change speed change ratio.

Abstract: A belt for a continuously variable transmission in which an aggregate of metal rings formed by laminating a plurality of pieces of endless metal rings support a plurality of metal blocks. When the ratio .xi. of the coefficient of friction is set to be 2.0>.xi.>0.65, the amount of change in the tension on the metal ring of the innermost position decreases correspondingly. In particular, when the ratio .xi. of the coefficient of friction is set to be 1.0, resulting in the coefficient of friction .mu..sub.s between a ring and a block being equal to the coefficient of friction .mu..sub.SS between a ring and a ring, the amount of change in the tension on all metal rings become uniform, and each metal ring shares an amount of change in the tension which is 8% of the entire amount. This makes it possible to decrease the amount of change in the tension on the metal ring of the innermost position and, hence, to increase the durability of the aggregate of metal rings as a whole.

Abstract: A process for presuming a power-transmitted state in a metal belt-type continuously variable transmission and for controlling axial thrust in a metal belt-type continuously variable transmission wherein it is presumed that a vector sum of friction coefficients .mu..sub.TDN and .mu..sub.RDN of a driven pulley is 0.1; a friction coefficient .mu..sub.RDR of a drive pulley is 0, and a friction coefficient .mu..sub.SDR or .mu..sub.SDN of the one of the pulleys which has a smaller winding radius is 0.1. A speed ratio i, a number N.sub.IN of rotations of the drive pulley, an input torque T.sub.IN to the drive pulley and an axial thrust Q.sub.DN of the driven pulley are measured, and the measured values are introduced into relational equations of the balance of forces on various portions of a metal belt-type continuously variable transmission. In this manner, an axial thrust Q.sub.DR of the drive pulley, urging forces E.sub.1 and E.sub.2 between the blocks and the pulleys, an axis-axis force FS, ring tensions T.sub.

Abstract: A metal V-belt type continuously variable transmission in which the length of a side of an element contacting with a V-face of a pulley is shortened to increase a ratio range. If the element side length of a metal element is represented by L, the angle of the V-face of the pulley is represented by .alpha., and the hertz surface pressure between the pulley and the metal element is represented by .sigma..sub.H, the following relation is established: L .varies. sin .alpha./.sigma..sub.H.sup.2. When the hertz surface pressure .sigma..sub.H is determined to be between an upper limit value defined by the wear durability of the metal element and a lower limit value defined by the limit tensile force of an endless belt, the element side length L can be decreased by decreasing the angle of the V-face of the pulley. Thus, the distance through which the metal element can be moved radially of the pulley is increased to increase the ratio range.

Abstract: In a metal V-belt type continuously variable transmission having a driving pulley and a driven pulley, the inclination angle .alpha. of a V-groove in the pulleys is set in a range represented by tan.sup.-1 .mu.a<.alpha.<tan.sup.-1 .mu.s, wherein .mu.s represents the static friction coefficient between the pulley and an endless belt, and .mu.a represents the dynamic friction coefficient between the pulley and the endless belt. In a conventional metal V-belt type continuously variable transmission, the inclination angle .alpha. is set in a range represented by .alpha.>tan.sup.-1 .mu.s. If the transmittable torque Tin is increased, the tensile force of the endless belt is increased to produce slipping between the endless belt and the pulley. However, according to the present invention, by decreasing the inclination angle .alpha. to reduce the tensile force of the endless belt, the transmittable torque Tin can be increased while preventing slipping of the endless belt.

Abstract: A belt-type continuously variable transmission has a drive pulley coupled to an input shaft, a driven pulley coupled to an output shaft, a V-belt trained around the drive and driven pulleys, a drive-pulley cylinder for varying the pulley width of the drive pulley, and a driven-pulley cylinder for varying the pulley width of the driven pulley.

Abstract: Disclosed is a metallic block for the detection of a force operating on a metallic V-belt. The metallic V-belt includes endless belt-like supporting straps and a multiplicity of metallic blocks supported along the straps. The V-belt passes around a driving pulley and a driven pulley. At least one of the multiplicity of metallic blocks comprises a notch formed in a part thereof, and a strain gauge attached to the notch. The strain gauge is intended to detect an external force applied to the metallic block. The force operating on the metallic V-belt is detected based on thus detected external force.

Abstract: A metallic V belt for use in a V-belt-type continuously variable transmission has an endless metallic belt strap and a plurality of metallic blocks each having a strap insertion slot defined therein and opening outwardly of the V belt at one side of the metallic block, the metallic blocks being mounted on that belt strap with the belt strap positioned in the strap insertion slots in the metallic blocks. A retaining belt strap or retainer is disposed in engagement with portions of the metallic blocks in covering relation to the endless belt strap in the strap insertion slots for retaining the metallic blocks against dislodgment from the belt strap. The retainer is in the form of an endless web having a flat transverse cross section and having at least one hole defined in the endless web. The hole in the endless web may be a slot, a narrow slit, or an elliptical hole.

Abstract: A power transmitting V-belt comprising an endless metal band mounted on supporting surfaces of a multiplicity of V-shaped metal blocks so linked to one another that adjacent blocks are rotatable relative to each other around an axis which is located substantially on the block contact surface of the band that engages the supporting surfaces of the metal blocks. This minimizes relative slippage between the metal band and the metal blocks during running of the V-belt.