Changing speed in a power transmission

A shifting mechanism for a multi-speed power transmission having a gear housing structure with an input shaft, an output shaft, and a plurality of changeable gears therein for changing the ratio of input to output speeds, said shifting mechanism comprising:

• (a) a first and second reduction shift rail movably mounted to said gear housing structure and slidably movable on a longitudinal direction between a fore and aft gear charge position;
• (b) an elongated final drive shaft rail slidably mounted on said gear housing structure and movable in the direction of elongation between first and second gear changing positions and disposed in spaced parallel arrangement with said first and second reduction shift rails;
• (c) a final drive shift fork secured to said final drive shift rail and movable therewith, adapted for effecting final drive gear ratio changes;
• (d) a first reduction shift fork slidably mounted on said first reduction rail and movable between said second and first reduction positions and adapted for effecting selected reduction gear ratio changes;
• (e) a second reduction shift fork slidably mounted on said second reduction rail between third and fourth reduction positions and adapted for effecting additional selected reduction gear ratio changes;
• (f) a slider guided for sliding movement on said first and second reduction shift rail;
• (g) a flipper member mounted for pivotal movement on said gear casing, said flipper having an end on one side of the pivotal mount engaging said final drive fork and the end on the side of said pivotal mount engaging said slider such that movement of said slider in one direction along said rails effects movement of said final drive fork in an opposite direction;
• and,
• (h) shift stick means pivotally mounted on said gear casing and operable upon selective user movement to effect movement of selected ones of said slides, said first shift fork and said second shift fork between said gear ratio position.

A shifting mechanism for a power transmission with an input shaft, an output shaft, and a plurality of changeable gears therein for changing the ratio of input shaft speed to output shaft in six forward speed ranges with an overdrive sixth speed range and a reverse speed range, said mechanism comprising:

• (a) housing structure;
• (b) first, second, third, and fourth elongated shift rails disposed in side-by-side spaced parallel arrangement in an array on said housing structure, each of said rails individually guided for sliding movement in the direction of elongation between a fore and aft speed change position;
• (c) a first shift fork secured to said first shift rail and movable therewith and adapted for effecting said reverse speed range upon movement to said aft position;
• (d) a second shift fork secured to said second shift rail for movement therewith between said fore and aft positions, said second shift fork adapted for effecting a first speed range in said aft position and a second speed range in said fore position;
• (e) a third shift fork secured to said third shift rail and movable therewith between said fore and aft positions, said third shift fork adapted to effect a third speed range in said aft position and a fourth speed range in said fore position;
• (f) a fourth shift fork secured to said fourth shift rail and movable therewith between said fore and aft positions, said fourth shift fork adapted for effecting a direct drive in said fore position and said sixth overdrive range in said aft position;
• (g) flipper means pivotally mounted for movement on said housing structure, said flipper disposed on one side of said array and having a first portion thereof on one side of said pivotal mount engaging said fourth shift fork;
• (h) block means mounted and guided for sliding movement on said fourth shift rail and movable between fore and aft positions, said block means operatively engaging a second portion of said flipper means disposed on the side of said pivotal mount opposite said first portion, wherein movement of said slider in one direction causes said fourth shift fork to move in an opposite direction;
• and,
• (i) shift stick means pivotally mounted for movement on said housing structure and disposed on the side of said array opposite said flipper means, said shift stick means operable upon user movement to selectively engage and move one of said first, second, and third shift forks and said slider between said fore and aft positions.

A shift mechanism for a change speed transmission having the final speed range as an overdrive, said mechanism comprising:

• (a) housing structure;
• (b) a plurality of elongated shift rails disposed in an array in spaced parallel relationship, each of said rails guided for sliding movement in the direction of elongation on said housing structure;
• (c) detent means operative to position each of said rails at a neutral position thereof;
• (d) a plurality of shift yoke means attached to one each of said rails and movable therewith in at least one direction from said neutral position;
• one of said yoke means adapted for effecting a next to last and final speed stage shift;
• (e) frame means pivoted on said housing structure and having portions on one side of said pivot operatively engaging said frame means and the end on the opposite side of said pivot operatively engaging said final stage shift yoke means for effecting movement thereof in a reverse direction in response to movement of said frame means in one direction, whereby neutral positioning of said final stage yoke means is determined by said final stage rail detent means.