GB705419A - A pre-setting apparatus for operating change speed mechanism, particularly for vehicles - Google Patents

Abstract

705,419. Controlling change-speed gearing. MASSAROTTI, M. July 3, 1951 [May 21, 1951], No. 15742/51. Class 80 (2) Gears are automatically pre-selected by a speed-responsive governor (not shown) acting through rod 106 and lever 104 on a cam bar 10<SP>1</SP> slidable longitudinally on guide pins 100, the engaged gear is disengaged on depression of the clutch pedal 70<SP>1</SP> and the pre-selected gear is engaged on the return movement of the pedal. Cams on one side of bar 10<SP>1</SP> operate a spring- loaded lever 16<SP>1</SP> connected through balanced springs 132 and rod 128 to an arm 126 on a shaft carrying a gear quadrant 122 engaging rack teeth on a rotatable disc 50<SP>1</SP> secured on a shaft. In the different axial positions of the latter, an arm 24<SP>1</SP> thereon engages one or other of three gearchange rods 120. Cams on the other side of bar 10<SP>1</SP> operate a spring-loaded lever 28<SP>1</SP> connected through balanced springs. 136 and rod 134 to a member 34', the lower end of which is pivoted to one arm of a bell-crank lever 146, the other arm of which is connected, through a lost motion device 150, 154 and rod 58<SP>1</SP>, to the pedal 70<SP>1</SP>. The upper end of member 34<SP>1</SP> co-operates with a pair of stop pins 88<SP>1</SP>, and the member 34' has recesses 142, 144 co-operating with pins 11.2, 114 on disc 50<SP>1</SP>. A manual lever 78<SP>1</SP>, co-operating with a notch M' on the pivot hub of lever 104, is provided for positioning bar 10' for reverse, neutral and forward drive, bar 10<SP>1</SP> having pairs of cams for reverse, neutral and four forward speeds. Fig. 1 shows the gear set at neutral, by lever 78', with the pedal 70' depressed, while Fig. 3 shows the position of the parts with fourth speed both pre-selected and engaged. The lost-motion device, comprising balls 160, Fig. 5, in holes in the wall of a hollow cylinder 154 connected to lever 146 and co-operating with annular grooves 158, 156 in a fixed guide sleeve 150 and in rod 58<SP>1</SP> enables the clutch to be disengaged before lever 146 is moved anti-clockwise from the position of Fig. 3, thus moving member 34' downwards and causing disc 50<SP>1</SP> to turn clockwise, since recess 144 is engaged with pin 114. This turning of disc 50<SP>1</SP>, and hence of arm 24<SP>1</SP>, causes the engaged fourth gear to be disengaged, enabling arm 24' to make the pre-selected axial movement. On releasing pedal 70<SP>1</SP>, lever 146 moves back clockwise before the clutch is engaged, causing member 34' to be moved upwards and producing rotation of disc 50<SP>1</SP> in . the pre-selected direction. and hence the engagement of the automatically pre-selected gear. An auxiliary spring 162 acts on lever 146 in such a way that it is ineffective when the pedal 70' is fully depressed but augments the clutch springs when the pedal is released. The pedal may be operated automatically by a servomotor controlled by the pre-selecting means. Specification 668,951 is referred to.