| 摘要 |
921,219. Fluid-pressure servomotor-control systems. FABBRICA ITALIANA MAGNETI MARELLI S.p.A. July 16, 1959 [July 16, 1958], No. 24490/59. Class 135. [Also in Group XXIV] In a power-assisted gear shift mechanism a shaft 26 is slid axially for gear selection by rotating a control-rod 10 and is rotated to establish a gear by a pneumatic servomotor on sliding the control-rod 10 axially. The rod 10 carries an arm 18 having a ball end 20 in a socket member 22 carried by an arm 24 of the shaft 26. On rotation of the rod 10 the shaft 26 is moved axially to bring a selected striker 42, 44, 46 carried by a stirrup 48 fast with the shafts into register with an associated fork 56, 58, 60 carried by shift-rods 50, 52, 54. On shifting the rod 10 axially the arm 18 engages a push-rod 70 or 71 actuating a valve 76 or 77 provided in a piston 64 to cut off a chamber C2 or C1 on either side of the piston from the atmosphere and open the chamber to pneumatic pressure. Play is provided in the socket member 22 to enable this to take place before the socket is moved by the ball 20. Movement of the piston 64 is transmitted by rollers 87 or 86 to the socket 22 to rotate the shaft 26 and engage the selected gear. Since the valves are mounted in the piston, the piston follows up the motion of the arm 18. If the servomotor is inoperative the shaft 26 is actuated directly when the play in the socket has been taken up. The control-rod 10 is retained in its axial positions by a spring-urged ball detent 14. The shaft 26 has recesses 36, 38, 40 which are respectively aligned with a selected shift-rod, the other rods being held stationary by full diameter portions of the shaft 26 engaging notches in these shift-rods. |
