Perfectionnements aux transmissions hydrauliques notamment pour véhicules automobiles

摘要

1,025,591. Change speed and reverse gear; clutch combinations; change speed and clutch control. FRANCAISE DU FERODO S.A. Jan. 9, 1963 [Jan. 9, 1962], No. 1062/63. Headings F2C, F2D and F2L. A hydromechanical reverse gear for a motor vehicle comprises two coaxial intermediate shafts 22, 221 respectively geared directly at 23, 24 and through an idler 26 to an output shaft and which shafts 22, 221 are, for forward and reverse ratios, selectively clutched at 19, 191 to the turbine T of a hydrodynamic torque converter C, the impeller P of which is fast with an input driven casing 12. As shown, a two-speed gear 80 is provided between the reverse gear and output shaft 11. Torque converter control.-The torque transmitted by the torque converter C is varied by inserting a baffle 50 into the working circuit. The converter casing 12 is supplied with liquid from a pump 38 at an intermediate pressure determined by a relief valve 70. The baffle 50 may, as shown, be moved left into the working circuit by supplying high pressure liquid from the pump 38 through a manually controlled valve 73 and line 67 to a servomotor 61. The baffle 50 is returned to the position shown by the intermediate pressure liquid in the casing 12 when the valve 73 vents the line 67 through a low pressure relief valve 77. In Fig. 1 (not shown) the baffle 50 is moved manually and may be linked to the vehicle brake pedal so that initial movement of the pedal operates the baffle and further movement of the pedal applies the brakes. Friction clutches and control.-The clutches 19, 191 may have slightly conical presses and reaction plates. As shown, the clutches are biased towards engagement by intermediate pressure liquid in a chamber 31 between the presser plates, which chamber 31 communicates with the interior of the casing 12 at 32. A clutch control valve 44 selectively supplies high pressure fluid from the pump 38 through lines 43, 431 to clutch chambers 41, 411 to oppose the intermediate pressure in chamber 31 and disengage the clutches. The valve 44 has three positions,one in which it supplies pressure liquid to both chambers 41, 411 to disengage both clutches 19, 191 and two others in which is supplied pressure liquid to one chamber 41 or 411 and vents the other 411 or 41. In Fig. 5 (not shown), an additional electromagnetically operated valve 85 connects both clutch chambers 41, 411 to the high pressure line to disengage the clutches during ratio shaft of the gear 80. In Fig. 1 (not shown) the clutches are biased towards a disengaged position by Belleville springs 28, 281 and orifices 30, 301 connect the chamber 31 with chambers 41, 411. The clutches are disengaged by blocking the outflow of liquid from the chambers 41, 411.