Dual-mode shifter for automatic transmissions

Claim 2

Transmission shifting apparatus, comprising a shift arm pivotable on an axis between at least two positions corresponding to different transmission output speed ranges, means for displacing said shift arm from one position to the other, including: a primary shift lever mounted to pivot between initial and terminal positions on another axis; and indexing means cooperable with said primary shift lever and said shift arm to pivot said arm in one direction from one position to the other upon pivotal movement of said primary shift lever, said indexing means including a slide element; means connecting said slide element to said shift arm to cause said shift arm to pivot upon displacement of said slide element; gripping means connected to said shift lever and engageable with said slide element upon pivotal movement of said shift lever in one direction about its axis and from its initial position for displacing said slide element; stop means associated with said gripping means to limit displacement of said gripping means and said slide engaged therewith upon continued pivotal movement of said shift lever in said one direction toward its terminal position; and biasing means for pivoting said shift lever in the opposite direction toward its initial position and about its axis to enable said gripping means to disengage said slide and to return said gripping means to a home position for re-engagement with said slide upon pivotal movement of said shift lever again from its initial position.

Claim 3

Apparatus according to claim 1 wherein said gripping means includes a housing slidably mounting said slide element, a carriage mounted in said housing to slide alongside said slide element, and a pawl mounted to pivot on an axis in said carriage for engaging said slide element and coupling said carriage and slide element to move together in said housing.

Claim 4

Apparatus according to claim 2 wherein said slide element has at least one recess confronting said pawl, and said pawl has a nose portion extending away from the pivot axis of the pawl and toward said shift arm and has a link portion extending away from the pivot axis of the pawl and at an angle with respect to said nose portion, and said gripping means including means coupling said link portion to said shift lever, whereby pivotal movement of said shift lever displaces said coupling means and pivots said link portion of said pawl to cause said nose portion of said pawl to engage in said recess for coupling said pawl and carriage and slide so that continued pivotal movement of said shift lever in said one direction pivots said shift arm from one position to the other.

Claim 5

Apparatus according to claim 3 wherein link portion of said pawl is disposed transversely to the path of movement of said slide and said coupling means extends between said link portion and said shift lever and substantially parallel to said path of movement of said slide, and said shift lever biasing means including a spring connected to said shift lever for biasing said shift lever toward its initial position and pivoting said pawl about its axis for disengaging said recess.

Claim 6

Apparatus according to claim 3 wherein said shift arm is sequentially movable from a first position corresponding to a first forward speed range through intermediate positions corresponding to at least second and third forward speed ranges and a neutral range and movable into a reverse speed range, and wherein said slide has a series of recesses corresponding in number to said intermediate ranges, said recesses being spaced one from the other in said slide element with the recess located remote from said shift arm corresponding to said neutral range, said slide element having a substantially smooth surface extending away from the remote recess in said series and confronting said pawl, so that when said slide element displaces said shift arm into its neutral range upon sequential piVotal movement of said primary shift lever, additional pivotal movement of said primary shift lever causes the pawl to engage said surface and to slide thereon to prevent further displacement of said slide element whereby inadvertent shifting into reverse range is prevented.

Claim 7

Apparatus according to claim 3 including surface means on said pawl and said slide in said recess engagable upon rapid displacement of said primary shift lever into its terminal position to prevent disengagement of said pawl from said recess due to inertia forces on said slide element.

Claim 8

Apparatus according to claim 6 wherein said surface means includes an internal surface in said recess disposed substantially normal to the path of movement of said slide and between the nose portion and pivot axis of said pawl, and an external surface on said nose portion of said pawl matingly engaging said internal surface when said nose portion is in said recess, whereby the pawl arrests inertial movement of the slide element.

Claim 9

Apparatus according to claim 2 wherein said stop means includes a forward stop member mounted in said housing in the path of movement of said carriage for engaging said carriage and arresting movement of said carriage and slide when said shift arm is shifted into its other position.

Claim 10

Apparatus according to claim 8 wherein said stop means further includes a rearward stop member spaced from said forward member and located in the path of movement of said carriage for engaging said carriage and arresting movement of said carriage when said primary shift lever is returned by said biasing means to its initial position from its terminal position.

Claim 11

Apparatus according to claim 1 wherein said shift arm extends in opposite directions away from its pivot axis, and including means pivotally fastening said slide element connecting means to said shift arm to one side of its axis to cause said shift arm to pivot in said one direction upon displacement of said primary shift lever, a secondary shift lever associated with said primary shift lever, and connecting linkage means coupling said secondary shift lever to said shift arm on the other side of its pivot axis, so that said secondary shift lever causes said shift arm to pivot in the opposite direction for effecting changes in said speed ranges.

Claim 12

Apparatus according to claim 10 including a master shift lever associated with said primary and secondary shift levers, frame means mounting said master shift lever to pivot relative to said primary and secondary shift levers, and selector means carried by said master shift lever for selectively coupling said master shift lever with said primary and secondary shift levers so that a shifting action is effected upon displacement of said master shift lever and through a selected one of said primary and secondary shift levers.

Claim 13

Apparatus according to claim 11 wherein said shift levers are mounted to said frame to pivot and wherein said selector means includes means providing a recess in each primary and secondary shift lever remote from their pivot axes, a selector pin selectively engagable in said recesses, and means mounting said selector pin for displacement relative to said master shift lever.

Claim 14

Apparatus according to claim 12 wherein said selector pin mounting means includes bifurcations on said master lever straddling said primary and secondary levers, an elongated slot in each of said bifurcations extending outwardly from the pivot axis of said master lever for slidably receiving said selector pin, elastic means carried on said master lever and connected to said selector pin for biasing said selector pin into said recesses to couple said master lever securely to a selected one of said primary and secondary shift levers, and including an operator mounted to said master shift lever for displacing said selector pin against its bias for selectively coupling and decoupling said pin with said primary and secondary shift levers.

Claim 15

Apparatus according to claim 13 wherein said master lever and said primary and secondary shift levers are mounted to said frame to pivot on a common axis and each of said primary and secondary shift levers has an extension extending outwardly of their pivot axis to a location corresponding substantially to the outermost terminus of the slot in each bifurcation, so that when said pin is displaced into its outer limit position in the slots, the shift lever extensions cooperate to prevent the pin from being displaced beyond the primary and secondary shift levers upon pivotal movement of the master shift lever in alternate directions.

Claim 16

Apparatus according to claim 14 including means providing a companion extension on said primary shift lever a spaced lateral distance from said first-mentioned extension thereon to define therebetween said recess, said companion extension terminating radially inward of the terminus of said first-mentioned extension a distance sufficient to permit passage of said pin into said recess when engaged at the terminus of its slots, and including abutment means carried by said frame and located outwardly of the common pivot axis and in substantial registry with said companion extension when said primary shift lever is in its initial position, said abutment means being located in the path of movement of said selector means to arrest motion of said master lever and primary shift lever when returning to its initial position.

Claim 17

Apparatus according to claim 11 including means mounting said primary and secondary shift levers to pivot relative to one another and said master shift lever, said primary and secondary shift levers being angulated with respect to one another in a plane normal to their pivot axis, said frame having a series of positioning surfaces each corresponding to a different transmission range and engagable by said selector means while coupled with said secondary shift lever, said position surfaces being located outwardly of said pivot axes and intermediate said axes and said selector means, and including guard means carried by said secondary shift lever and located outwardly of said axes a distance greater than the corresponding distance of said positioning surfaces, said guard means extending toward said primary shift lever from said secondary shift lever, so that when the selector means is disengaged from the primary shift lever for engagement with the secondary shift lever, the guard means engages the selector means and prevents said selector means from engaging positioning surfaces corresponding to speed ranges other than the range into which the transmission was last shifted by the primary shift lever.

Claim 18

Apparatus according to claim 16 wherein said frame has a latch spaced from said series of index surfaces for receiving said selector means when said master lever is coupled with said secondary shift lever, said latch releasably securing said master lever in a position corresponding to a transmission locking position, and including camming means on said frame engagable by said selector means to urge said selector means into said latch upon displacement of said master shift lever in a direction toward said latch.

Claim 19

Transmission shifting apparatus, comprising a shift arm pivotable on an axis between at least two positions corresponding to different transmission output speed ranges, means for displacing said shift arm from one position to the other, including: a primary shift lever mounted to pivot between initial and terminal positions on another axis; and indexing means cooperable with said primary shift lever and said shift arm to pivot said arm in one direction from one position to the other upon pivotal movement of said primary shift lever, said indexing means including a displaceable element; means connecting the displaceable element to said shift arm to cause said shift arm to pivot upon displacement of said displaceable element; gripping means connected to said shift lever and engagable with said displaceable element upon pivotal movement of said shift lever in one directIon about its axis and from its initial position for displacing said displaceable element; stop means associated with said gripping means to limit displacement of said gripping means and said displaceable element engaged therewith upon continued pivotal movement of said shift lever in said one direction toward its terminal position; complementary stop means for arresting movement of said primary shift lever at its initial position when said primary shift lever is displaced in the opposite direction after effecting displacement of said shift arm, a master lever associated with said primary shift lever, frame means mounting said master lever to pivot relative to said primary shift lever, and selector means carried by said master shift lever for selectively coupling said master lever with said primary lever and uncoupling said master lever from said primary lever.

Claim 20

Transmission shifting apparatus, comprising a shift arm pivotable on an axis between at least two positions corresponding to different transmission output speed ranges, means for displacing said shift arm from one position to the other, including: a primary shift lever mounted to pivot between initial and terminal positions on another axis; and indexing means cooperable with said primary shift lever and said shift arm to pivot said arm in one direction from one position to the other upon pivotal movement of said primary shift lever, said indexing means including a displaceable element; means connecting the displaceable element to said shift arm to cause said shift arm to pivot upon displacement of said displaceable element; gripping means connected to said shift lever and engagable with said displaceable element upon pivotal movement of said shift lever in one directIon about its axis and from its initial position for displacing said displaceable element; stop means associated with said gripping means to limit displacement of said gripping means and said displaceable element engaged therewith upon continued pivotal movement of said shift lever in said one direction toward its terminal position; complementary stop means for arresting movement of said primary shift lever at its initial position when said primary shift lever is displaced in the opposite direction after effecting displacement of said shift arm, a master lever associated with said primary shift lever, frame means mounting said master lever to pivot relative to said primary shift lever, and selector means carried by said master shift lever for selectively coupling said master lever with said primary lever and uncoupling said master lever from said primary lever.