Patent GB-411551-A (GB)
Title: Improvements in and relating to gear-shift mechanism
IPC: F16H59/04
Filed: 1932-12-16
Abstract: 411,551. Controlling variable-speed gearing. ROGERS, B. H., 28, Park Hill, Harpenden, Hertfordshire, and VAUXHALL MOTORS, Ltd., Kimpton Road, Luton. Dec. 16, 1932, No. 35724. [Class 80 (ii).] In a four-speed and reverse gear, the lower end of a universally-mounted hand lever 2, Figs. 1, 2, engages an aperture in a horizontallyarranged lever 5 provided at each end with a pin 17. The upper ends of the pins co-operate with slots 20, 21 in the arcuate ends of a locking plate 10 which is guided by fixed pins 11, 12 for limited endwise movement against springs 14. With the parts in neutral position, both pins 17 lie partially within the slots 20, 21 and their lower ends engage grooves 18, 19 in the forward selector forks 6, 7, whereby the latter are locked. To obtain forward drives, lever 5 is moved endwise so as fully to engage the trailing pin 17 in its slot 20 or 21 and to disengage the leading pin from its slot, both pins remaining engaged in the grooves 18, 19. Thus the lever 5 may now pivot about the trailing pin 17 to move one of the forks 6, 7, the other fork remaining locked. To obtain reverse drive, the lever 5 is moved endwise to the left, Fig. 1, to such an extent that the trailing pin 17 causes the plate 10 also to move against the springs 14 until the leading pin 17 disengages from the groove 18 in the fork 6 and engages a groove 23 in the reverse fork 8, the trailing pin 17 remaining engaged in the groove 19. The lever 5 may now pivot about the trailing pin to move the fork 8, the fork 7 remaining locked. To ensure that either of the forks 6, 8 is locked when the other is moved, a plunger 26, Fig. 3, co-operates with notches 27 in the rods 24, 25 carrying the forks ; or the plate 10 may be provided with a pair of side lugs and an end lug, similar to those shown at 32 and 33, Fig. 6, such that the lug 33 normally locks the fork 8 while the lugs 32 lock the fork 6 when the fork 8 is being actuated. The locking plate may be associated with oppositely-acting springs so as to enable eight gear changes to be effected. In a modification, the plate 10, Fig. 6, is fixed and an additional plate 10<A> capable of limited endwise movement against a spring 30 is provided, the plate 10<A> being provided with the lugs 32, 33 and being caused to move endwise against the spring 30, when it is desired to obtain reverse, by the leading end of the lever 5. In another modification, the slots 20, 21, Fig. 8, are in the outer edges of arcuate slots in the plate 10, whereby the leading pin 17 forms the pivot. In a three-speed and reverse gear, the locking plate 10, Figs. 9, 10, is movable endwise by the lever 2, which engages a transverse slot 38 in the plate and a longitudinal slot 39 in the lever 5, the latter having end pins 17 which engage T-shaped slots in the plate 10 and against which a pair of fixed arcuate lugs 37 permanently bear. Upon movement of the lever 2, the plate 10 is moved endwise until the lever 5 can pivot about the trailing pin to move one or other of the forks 35, 36. To adapt this construction for additional speeds, one or both of the lugs 37 is resiliently mounted so as to provide for endwise movement of the lever 5.