Extreme ratio overdrive power transmission mechanism

Claim 2

An overdrive power transmission mechanism adapted to deliver driving torque from an engine to a driven member including a hydrokinetic torque converter having a bladed impeller and a bladed turbine situated in toroidal fluid flow relationship, planetary gearing comprising first and second simple planetary gear units, each gear unit comprising a ring gear, a sun gear, a carrier and planet pinions journaled rotatably on said carrier, a compound planetary gear unit comprising a ring gear, two sets of planet pinions, a carrier journaling each set of pinions, one of said sets of pinions engaging drivably said ring gear, said compound planetary gear unit including also a sun gear drivably engaged with the other of said sets of pinions, said sets of pinions being engageable with each other, the sun gears of said gear units being connected together for rotation in unison, the ring gear of said second simple planetary gear unit being connected to said driven member, means for anchoring the carrier for said second simple planetary gear unit to provide a reaction point during low speed ratio operation, brake means for anchoring the sun gear of said first simple planetary gear unit during intermediate-speed ratio operation and during overdrive ratio operation, selectively engageable clutch means for connecting drivably said turbine to the ring gear of said first simple planetary gear unit during operation in a low speed ratio, an intermediate-speed ration and a high speed ratio, second selectively engageable clutch means for connecting together the ring gear of said compound planetary gear unit and said turbine during overdrive ratio operation with the driven member being overspeeded with respect to the driving speed of the engine, and clutch means for connecting directly the converter impeller and the converter turbine to establish a mechanical drive between said engine and the ring gear of said compound planetary gear unit during overdrive operation.

Claim 3

An overdrive power transmission mechanism adapted to deliver driving torque from an engine to a driven member including a hydrokinetic torque converter having a bladed impeller and a bladed turbine situated in toroidal fluid flow relationship, planetary gearing comprising first and second simple planetary gear units, each gear unit comprising a ring gear, a sun gear, a carrier and planet pinions journaled rotatably on said carrier, a compound planetary gear unit comprising a ring gear, two sets of planet pinions, a carrier journaling each set of pinions, one of said sets of pinions engaging drivably said ring gear, said compound planetary gear unit including also a sun gear drivably engaged with the other of said sets of pinions, said sets of pinions being engageable with each other, the sun gears of said gear units being connected together for rotation in unison, the ring gear of said second simple planetary gear unit being connected to said driven member, means for anchoring the carrier for said second simple planetary gear unit to provide a reaction point during low speed ratio operation, brake means of anchoring the sun gear of said first simple planetary gear unit during intermediate-speed ratio operation and during overdrive ratio operation selectively engageable clutch means for connecting drivably said turbine to the ring gear of said first simple planetary gear unit during operation in a low speed ratio, an intermediate-speed ratio and a high-speed ratio, second selectively engageable clutch means for connecting together the ring gear of said compound planetary gear unit and said turbine during operation in an overdrive ratio with the driven member being overspeeded with respect to the driving speed of the engine, and clutch means for connecting converter impeller and the converter turbine to establish a mechanical drive between said engine and the ring gear of said compound planetary gear unit during overdrive ratio operation, overrunning coupling means for establishing a one-way torque delivery path between the ring gear of said first planetary gear unit and said turbine when said second clutch means is applied whereby an automatic upshift from a direct drive ratio to an overdrive ratio is accompanied by an overrunning motion of the ring gear of said first simple planetary gear unit with respect to said turbine and said second clutch means remains applied during an upshift to the overdrive ratio.

Claim 4

An overdrive power transmission mechanism adapted to deliver driving torque from an engine to a driven member including a hydrokinetic torque converter having a bladed impeller and a bladed turbine situated in toroidal fluid flow relationship, planetary gearing comprising first and second simple planetary gear units, each gear unit comprising a ring gear, a sun gear, a carrier and planet pinions journaled rotatably on said carrier, a compound planetary gear unit comprising a ring gear, two sets of planet pinions, a carrier journaling each set of pinions, one of said sets of pinions engaging drivably said ring gear, said compound planetary gear unit including also a sun gear drivably engaged with the other of said sets of pinions, said sets of pinions being engageable with each other, the sun gears of said gear units being connected together for rotation in unison, the ring gear of said second simple planetary gear unit being connected to said driven member, means for anchoring the carrier for said second simple planetary gear unit to provide a reaction point during low speed ratio operation, brake means of anchoring the sun gear of said first simple planetary gear unit during intermediate-speed ratio operation and during overdrive ratio operation selectively engageable clutch means for connecting drivably said turbine to the ring gear of said first simple planetary gear unit during operation in a low speed ratio, an intermediate-speed ratio and a high-speed ratio, second selectively engageable clutch means for connecting together the ring gear of said compound planetary gear unit and said turbine during operation in an overdrive ratio with the driven member being overspeeded with respect to the driving speed of the engine, and clutch means for connecting converter impeller and the converter turbine to establish a mechanical drive between said engine and the ring gear of said compound planetary gear unit during overdrive ratio operation, overrunning coupling means for establishing a one-way torque delivery path between the ring gear of said first planetary gear unit and said turbine when said second clutch means is applied whereby an automatic upshift from a direct drive ratio to an overdrive ratio is accompanied by an overrunning motion of the ring gear of said first simple planetary gear unit with respect to said turbine and said second clutch means remains applied during an upshift to the overdrive ratio.

Claim 5

The combination as set forth in claim 1 wherein said compound planetary gear unit is intermediate the two simple planetary gear units in a common gear assembly, the second of said simple planetary gear units being axially positioned furthermost with respect to the other gear units from said hydrokinetic torque converter.

Claim 6

The combination as set forth in clAim 3 wherein each of said gear units has a common sun gear, the planet pinions for each gear unit engaging separate portions of said common sun gear at axially spaced locations.

Claim 7

The combination as set forth in claim 2 wherein said compound planetary gear unit is intermediate the two simple planetary gear units in a common gear assembly, the second of said simple planetary gear units being axially positioned furthermost with respect to the other gear units from said hydrokinetic torque converter.

Claim 8

The combination as set forth in claim 5 wherein each of said gear units has a common sun gear, the planet pinions for each gear unit engaging separate portions of said common sun gear at axially spaced locations.