Extended range hydraulic transmission

Claim 1

output speed or torque output. 13. An extended range hydraulic transmission comprising input means, hydraulic transmission means including a pair of separate hydraulic elements, means providing hydraulic communication between said elements, one of said hydraulic elements being drivingly connected with said input means, output planetary gearing including a plurality of members, the other of said hydraulic elements being drivingly connected with one of the members of said output planetary gearing, output means, another member of said output planetary gearing being drivingly connected with said output means, means providing a driving connection between said input means and a third member of said output planetary gearing, said last-mentioned driving connection including selectively engageable and disengageable means for connecting or disconnecting said third member from said input means, fixed means, and selectively engageable and disengageable means for operatively connecting a fourth member of said planetary gearing with said fixed means for holding said fourth member against movement. 14. Apparatus as defined in claim 13 including power take-off means, and selectively engageable and disengageable means for connecting or disconnecting said power take-off means with said driving connection between said input means and said third member of the output planetary gearing. 15. An extended range hydraulic transmission comprising an input shaft, an output shaft, hydraulic transmission means including a pair of separate hydraulic elements, means providing hydraulic communication between said elements, one of said hydraulic elements being drivingly connected with and in concentric relation to said input shaft, output planetary gearing including a plurality of members, one of said members of said output planetary gearing being drivingly connected with another of said hydraulic elements, said output shaft being drivingly connected with another of said members of the output planetary gearing, an auxiliary shaft, means drivingly connecting said auxiliary shaft with said input shaft, selectively engageable and disengageable means for drivingly connecting said auxiliary shaft to a third member of said output planetary gearing, fixed means, and selectively engageable and disengageable means for operatively connecting a fourth member of said planetary gearing with said fixed means for holding said fourth member against movement. 16. Apparatus as defined in claim 15 including a power take-off shaft disposed in substantial alignment with said auxiliary shaft and in spaced parallel relationship to said input shaft, and selectively engageable and disengageable means for drivingly connecting said power take-off shaft with said auxiliary shaft. 17. An extended range hydraulic transmission comprising an input shaft, an intermediate shaft substantially aligned with said input shaft an output shaft substantially aligned with said intermediate shaft, hydraulic transmission means including a pair of separate hydraulic elements, means providing hydraulic communication between said elements, one of said hydraulic elements being drivingly connected with said input shaft, another of said hydraulic elements being drivingly connected with said intermediate shaft, output planetary gearing comprising a plurality of members, one of said members of the output planetary gearing being drivingly connected with said intermediate shaft, said output shaft being drivingly connected with another of said members of said output planetary gearing, an auxiliary shaft disposed in spaced parallel relation to said input shaft, intermediate shaft and output shafts, means drivingly connecting said auxiliary shaft with said input shaft, selectively engageable and disengageable means for operatively connecting said auxiliary shaft to a third member of said output planetary gearing, fixed means, a selectively engageable and disengageable means for operatively connecting a fourth member of the output planetary gearing to said fixed means for holding said last-mentioned member of the output planetary gearing against movement. 18. Apparatus as defined in claim 17 including a power take-off shaft disposed in substantial alignment with said auxiliary shaft and in spaced parallel relationship to said input shaft, intermediate shaft and output shaft, and selectively engageable and disengageable means for drivingly connecting said power take-off shaft with said auxiliary shaft. 19. An extended range hydraulic transmission comprising an input shaft, an auxiliary shaft substantially in line with said input shaft, an intermediate shaft disposed in spaced parallel relation to said input shaft, an output shaft substantially aligned with said intermediate shaft, hydraulic transmission means including a pair of separate hydraulic elements, means providing hydraulic communication between said elements, one of said hydraulic elements being drivingly connected with said input shaft, another of said hydraulic elements being drivingly connected with said intermediate shaft, output planetary gearing comprising a plurality of members, one of said members of said output planetary gearing being drivingly connected with said intermediate shaft, said output shaft being drivingly connected with another of said members of the output planetary gearing, means drivingly connecting said auxiliary shaft with said input shaft, selectively engageable and disengageable means for operatively connecting said auxiliary shaft to a third member of said output planetary gearing, fixed means, a selectively engageable and disengageable means for operatively connecting an additional planetary gear element of the output planetary gearing to said fixed means for holding said last-mentioned element of the output planetary gearing against movement. 20. An extended range hydraulic transmission comprising an input shaft, an output shaft, hydraulic transmission means including a pair of separate hydraulic elements, means providing hydraulic communication between said elements, one of said hydraulic elements being drivingly connected with said input shaft, output planetary gearing comprising a plurality of members, said output planetary gearing including sun gear means drivingly connected with another of said hydraulic elements, said output planetary gearing including carrier means and planet gear means rotatably supported by said carrier means, said planet gear means being in meshing engagement with said sun gear means, said carrier means being drivingly connected with said output shaft, said output planetary gearing including first ring gear means, said first ring gear means being in meshing engagement with said planet gear means, fixed means, selectively engageable and disengageable means for operatively connecting said first ring gear means to said fixed means for holding said first gear means against rotation, an auxiliary shaft, means drivingly connecting said auxiliary shaft with said input shaft, said output planetary gearing including an additional planetary gear element, and selectively engageable and disengageable means for drivingly connecting said auxiliary shaft with said additional gear means. 21. Apparatus as defined in claim 20 wherein said additional gear means comprises second ring gear means and second planet gear means in meshing engagement with said second ring gear means. 22. Apparatus as defined in claim 21 wherein said second ring gear means is formed integral with said carrier means. 23. Apparatus as defined in claim 20 wherein said additional gearing includes second ring gear means, second planetary gear means carried by said carrier means, and said second ring gear means being in meshing engagement with said second carrier means. 24. An extended range hydraulic transmission comprising an input shaft, an intermediate shaft substantially aligned with said input shaft, an output shaft substantially aligned with said intermediate shaft, hydraulic transmission means including a pair of separate hydraulic elements, means providing hydraulic communication between said elements, one of said hydraulic elements being drivingly connected with said input shaft, output planetary gearing comprising a plurality of members, said output planetary gearing including a pair of sun gear means, each of said sun gear means being drivingly connected with said intermediate shaft which is in turn drivingly connected with another of said hydraulic elements, said output planetary gearing including first carrier means, said first carrier means being drivingly connected with said output shaft, planetary gear means rotatably supported by said first carrier means and being in meshing engagement with one of said sun gear means, first ring gear means in meshing engagement with said planetary gearing means, fixed means, selectively engageable and disengageable means for operatively connecting said first ring gear means with sadi fixed means for holding said first ring gear means against movement, second ring gear means formed integral with said first carrier means, second carrier means, second planet gear means in meshing engagement with said second ring gear means and also being in meshing engagement with another of said sun gear means, an auxiliary shaft disposed in spaced parallel relation to said input shaft, intermediate shaft and output shafts, means drivingly connecting said auxiliary shaft with said input shaft, and selectively engageable and disengageable means for operatively connecting said auxiliary shaft with said second carrier means. .Iadd. 25. In a power train, in combination an input shaft, an output shaft, .[..[..Iadd.speed differential.Iaddend..]..]. .Iadd.output .Iaddend..Badd.planetary .Baddend..Iadd.gear means connected to said output shaft .Iaddend..Badd.for selectively driving said output shaft in a continuously variable reverse and low forward speed range stage of operation and in a continuously variable extended high forward speed range stage of operation .Baddend..Iadd.and including two separate drive input members drivingly interconnected with one another, first drive transmitting means .Iaddend..Badd.connecting said input shaft to a first one of said drive input members for driving said output planetary gear means both during said reverse and low forward speed range stage of operation and during said extended high forward speed range stage of operation and .Baddend..Iadd.including .Iaddend..[..[..Iadd.hydrostatic.Iaddend..]..]. .Badd.hydraulic .Baddend..Iadd.transmission means drivingly connected to said input shaft and .[..[..Iadd.a.Iaddend..]..]. .Badd.to said .Baddend..Iadd.first one of said separate drive input members .Badd.for driving said first drive input member variably, relative to unidirectional rotational speed of said input shaft, between a first relative speed in one direction of rotation and a second relative speed in the opposite direction of rotation.Baddend..Iadd., second drive transmitting means .Iaddend..Badd.connected to said input shaft and to the other one of said drive input members for driving said output planetary gear means only during said extended high forward speed range stage of operation and .Baddend..Iadd.including a first engageable and disengageable means for drivingly connecting and disconnecting said input shaft to said .Iaddend..[..[..Iadd.second.Iaddend..]..]. .Badd.other .Baddend..Iadd.one of said separate drive input members, second engageable and disengageable means operatively connected with the output .Iaddend..Badd.planetary .Baddend..Iadd.gear means and cooperating with said first engageable and disengageable means for converting said output .Iaddend..Badd.planetary .Baddend..Iadd.gear means to drive said output shaft in either one of .Iaddend. .[..[..Iadd.two conditions.Iaddend..]..]. .Badd.said stages of operation .Baddend..Iadd., the .Iaddend..[..[..Iadd.first condition.Iaddend..]..]. .Badd.reverse and low forward speed range stage of operation .Baddend..Iadd.being a single input drive condition .Iaddend..Badd.allowing continuously variable reverse and low forward speed rotation of said output shaft as said first drive input member is varied in its relative speed of rotation from said first relative speed to said second relative speed .Baddend..Iadd.wherein said first drive input member drives both said output shaft and said .Iaddend..[..[..Iadd.second.Iaddend..]..]. .Badd.other .Baddend..Iadd.drive input member with said .Iaddend..[..[..Iadd.second.Iaddend..]..]. .Badd.other .Baddend..Iadd.second input drive member being driven by said first drive input member, the .Iaddend..[..[..Iadd.second condition.Iaddend..]..]. .Badd.extended high speed range stage of operation .Baddend..Iadd.being a dual input drive condition wherein said first and .[..[..Iadd.second.Iaddend..]..]. .Badd.other .Baddend..Iadd.drive input members differentially drive said output shaft .Iaddend..Badd.to effect continuously variable extended high forward speed range rotation of said output shaft as said first drive input member is varied in its relative speed of rotation from said second relative speed back toward said first relative speed.Baddend..Iadd., said first engageable and disengageable means being engaged under synchronous conditions when said output .Iaddend..Badd.planetary .Baddend..Iadd.gear means is converted to said .Iaddend..[..[..Iadd.second condition.Iaddend..]..]. .Badd.extended high forward speed range stage of operation .Baddend..Iadd.and said first engageable and disengageable means being disengaged under synchronous conditions when said output .Iaddend..Badd.planetary .Baddend..Iadd.gear means is converted to said .Iaddend..[..[..Iadd.first condition.Iaddend..]..]. .Badd.reverse and low forward speed range stage of operation..Baddend. .Iadd. 26. Apparatus as defined in claim 25 wherein said first engageable and disengageable means for drivingly connecting and disconnecting said .Iaddend..[..[..Iadd.second.Iaddend..]..]. .Badd.other .Baddend..Iadd.drive transmitting means under synchronous conditions comprises clutch means. .Iaddend..Iadd. 27. Apparatus as defined in claim 25 wherein said second engageable and disengageable means .Iaddend..Badd.operatively connected with said output planetary gear means and cooperating with said first engageable and disengageable means .Baddend..Iadd.for converting said output .Iaddend..Badd.planetary .Baddend..Iadd.gear means .Iaddend..[..[..Iadd.between said first and second drive conditions.Iaddend..]..]. .Badd.to drive said output shaft in either one of said stages of operation .Baddend..Iadd.comprises brake means. .Iaddend..Iadd. 28. Apparatus as defined in claim 25 wherein said .Iaddend..[..[..Iadd.hydrostatic.Iaddend..]..]. .Badd.hydraulic .Baddend..Iadd.transmission means drives said first one of said separate drive input members at a variable speed ratio with respect to the input shaft, said second drive transmitting means driving the other input member from said input shaft at a fixed speed ratio with respect thereto when said first engageable and disengageable means is engaged. .Iaddend. .Iadd. 29. Apparatus as defined in claim 25 wherein said first drive transmitting means includes a drive shaft which .Iaddend..[..[..Iadd.may be.Iaddend..]..]. .Badd.is .Baddend..Iadd.driven .Iaddend..[..[..Iadd.at different speed ratios.Iaddend..]..]. .Badd.between said first and second relative speeds .Baddend..Iadd.with respect to said input shaft, said second drive transmitting means including a drive member driven at fixed speed ratio with respect to said input shaft, so that in said .Iaddend..[..[..Iadd.first condition.Iaddend..]..]. .Badd.reverse and low forward speed range stage of operation .Baddend..Iadd.of said output .Iaddend..Badd.planetary .Baddend..Iadd.gear means both said output shaft and said .Iaddend..[..[..Iadd.second.Iaddend..]..]. .Badd.other drive .Baddend..Iadd.input member are driven at speeds which are proportional to the speed of said drive shaft but which may vary in speed ratio with respect to said input shaft, whereby at a predetermined speed ratio between said input shaft and said drive shaft the speeds of said .Iaddend..[..[..Iadd.second.Iaddend..]..]. .Badd.other drive .Baddend..Iadd.input member and said drive member of the second drive .Iaddend..Badd.transmitting .Baddend..Iadd.means are synchronized such that said first engageable and disengageable means can be engaged under synchronous conditions when said output gear means is converted to said .Iaddend..[..[..Iadd.second condition.Iaddend..]..]. .Badd.extended high forward speed range stage of operation .Baddend..Iadd.as said predetermined speed ratio .Iaddend..Badd.between said input shaft and said drive shaft .Baddend..Iadd.is achieved. .Iaddend.