Control apparatus for belt-type continuously variable transmission

摘要

A control apparatus for a belt-type continuously variable transmission having a drive pulley (11), a driven pulley (16), a V-belt (15) trained around said drive and driven pulleys (11,16), a drive cylinder (14) for varying a pulley width of said drive pulley (11), and a driven cylinder (19) for varying a pulley width of said driven pulley (16), comprising: a pressure regulator valve (40;140) for producing pulley control pressures to be supplied to said drive and driven cylinders (14,19); a shift valve (53;153) for distributing said pulley control pressure to said drive and driven cylinders (14, 19) to regulate drive and driven cylinder pressures in said drive and driven cylinder (14,19) for a speed ratio control; electric shift control means (51;151) for operationally controlling said shift valve (53;153) by means of an electric power; and means (50;150) for allowing said electric shift control means (51;151) to make pressures in both said drive cylinder (14) and said driven cylinder (19) equal with each other when said electric power is lost.