Patent GB-429778-A (GB)
Title: Improvements in and relating to control mechanism for change speed gearing
IPC: F16H61/02
Filed: 1933-12-21
Abstract: 429,778. Controlling change speed gearing. RENAULT, L., 8, Avenue Emile Zola, Billancourt, Seine, France. Dec. 21, 1933, No. 36043. Convention date, Jan. 30. [Class 80 (ii)] Preselection is effected by moving a preselector arm 13, Fig. 2, upon a transverse pivot 12 on the control shaft 1 of the engine clutch of, say, a vehicle, the change being carried out by disengaging and re-engaging the clutch preferably by depressing and releasing a button controlling an engine suction servomotor, not shown, adapted to rock the clutch disengaging shaft 1. This servomotor acts through a loose lever 3 and a fast lever 4 on the shaft 1 which through a cam 7, bowl lever 8, shaft 9, and fork 10 disengages the clutch C, Fig. 1, The preselector lever 13 has one or more fingers 14, 15 which are operative in one direction only of rocking of the shaft 1 to traverse one or more selector bars 24, 25 both ways. The bar 25 is operable by two levers 28 and 32 pivoted respectively as shown in Fig. 3 at 27 above the bar and at 34 below the bar so that the bar is traversed in one direction or the other according to which of the levers 28, 32 is engaged by the finger 14 as it is rocked left of Fig. 3 by power. Fig. 3 shows the position with second gear and the engine clutch both engaged. A spring pawl 36 carried by the preselector lever 13 engages over a heel 39 upon an auxiliary lever frame 40 which rests against a stop 43. The frame 40 has a cross-pin 42 which runs along the backs of all four bar-actuating levers 28, 32, 29, 33. To change to third speed, for example, the driver by releasing a Bowden wire 132 from a suitable selector handle, not shown, sets the finger 15 opposite the lower end of the lever 29. The lever 13 turns freely over a spring pawl 17 internal to a notched quadrant 16 which holds the lever 13 in position. The driver then depresses the button of the servomotor which rocks the shaft 1 left of Figs. 3 and 5. As the clutch is taken out, the pawl 36, Fig. 3, depresses the heel 39 so that the frame 40 rocks right and the crosspin 42 brings all four levers 28, 32, 29, 33 to the neutral vertical position shown in Fig. 1. As the shaft 1 continues its leftward rock, the pawl 36 slips clear of the heel 39 and the finger 15 carries the lever 29 with it to the position shown in Fig. 5 with the bar 24, Fig. 1, moved left to engage a directdrive gear-cutch. During the rock from the position of Fig. 1 to that of Fig. 5, a fixed projecting cam 44 engages over a tail of the lock pawl 17 preventing that pawl from unlocking the preselector lever 13. On the servomotor button being released, the shaft 1 and the parts it carries rock back from the position of Fig. 5 to that of Fig. 3, letting in the main clutch and releasing the constraint on the lock pawl 17 so that the lever 13 may be reset for another speed change. A lever 6, Fig. 2, is provided for manual operation of the shaft 1 of the main clutch. Sliding gears in the transmission as well as the preselector lever 13 may be connected to suitable indicating means to show their position at any time. The transmission shown in Fig. 1 has a pair of synchronized clutches D for the two highest speeds, but such clutches may be used throughout.