Multiple speed range hydromechanical transmission

Claim 2

An infinitely variable hydromechanical transmission providing three synchronously changeable speed ranges, each with a distinct torque ratio between the output of the hydrostatic transmission and the output shaft, comprising: a. an input means (1); b. an output shaft (60); c. an intermediate shaft (36); d. a variable speed hydrostatic transmission (2) interposed between said input means (1) and said intermediate shaft (36) whereby said hydrostatic transmission is driven by said input means and said intermediate shaft is driven by said hydrostatic transmission; e. selectable reduction gearing means (5) interconnecting said intermediate (36) and output (60) shafts; f. a first three-element epicyclic gear set (6) having a first element (38) driven by the intermediate shaft (36), a second element (64) provided with transfer means (67) to drive an element of a second three-element epicyclic gear set and a third element (62, 66) to complete the first epicyclic set; g. a second three-element epicyclic gear set (7) having a first element (70) provided with a transfer means (71) driven by said transfer means (67) of said first epicyclic set, a second element (72, 76) connected to said output shaft (60) and a third element (74) connected to said input means (1) by mechanical means (75, 78) for transfer of input torque; and h. clutch means (44, 69) operatively connected with said first epicyclic set for i. selectively locking the third element (62, 66) of said first set to ground to form a reaction point in said set to employ the gear ratio between the first (38) and the second (64) elements of the first set as reduction gearing between said intermediate shaft (36) and said transfer means (71) of said second epicyclic set, ii. selectively locking together two elements of said first set to cause common rotation of all three elements of said first set; whereby said first and second epicyclic sets provide two ranges of different torque ratios between said hydrostatic transmission and said output shaft, each of which ratios is different from that provided by said selectable reduction gearing means (5) which provides a third range having a distinct torque ratio.

Claim 3

The transmission of claim 1 wherein: a. said first three-element epicyclic set (6) comprising a sun gear (38) connected to said intermediate shaft (36), planetary gears (62) supported by carrier (66) and a ring gear (64) carrying a spur gear (67), said sun gear being said first element, said ring gear being said second element, said spur gear being said transfer means and said planetary gears and carrier being said third element; b. said second three-element epicyclic set comprising as said first, second and third elements respectively a ring gear (70) having an exterior spur gear (71) meshing with the said exterior spur gear (67) of said first set, planetary gears (72) mounted on a carrier (76) connected to said output shaft (60), and sun gear (74) connected to a shaft (75) comprising a portion of said mechanical means for transfer of input torque; and c. said clutch means comprising: i. an intermediate range brake (68) for locking said carrier (66) of said first set to ground to provide a reaction means for applying the gear ratio existing between said sun gear (38) and ring gear (64) as a reduction ratio between said intermediate shaft (36) and said second epicyclic set, and ii. a high range clutch mechanism (69) for locking said sun gear (38) to said ring gear (64) of said first epicyclic set to cause the common rotation of said three elements of said first set.

Claim 4

The transmission of claim 2 wherein said variable speed hydrostatic transmission (2) is connected to said intermediate shaft (36) by means of differential gearing (3) having two inputs (30, 32) and one output (35), said output (35) being connected to said intermediate shaft (36), the first said input (32) being connected to the output of said hydrostatic transmission and the second said input (30) being connected to said input means whereby said hydrostatic transmission is made to operate as a hydromechanical transmission.

Claim 5

The transmission of claim 1 wherein said variable speed hydrostatic transmission (2) is connected to said intermediate shaft (36) by means of differential gearing (3) having two inputs (30, 32) and one output (35), said output (35) being connected to said intermediate shaft (36), the first said input (32) being connected to the output of said hydrostatic transmission and the second said input (30) being connected to said input means whereby said hydrostatic transmission is made to operate as a hydromechanical transmission.

Claim 6

The transmission of claim 4 wherein said selectable reduction gearing means (5) interconnecting said intermediate (36) and said output (60) shafts comprises a low range gear train (42, 50, 52) driven by said intermediate shaft, a low range clutch (48), a reverse range gear train (40, 82, 52) driven by said intermediate shaft, a reverse range clutch (46), and spur gears (56, 58) connecting the output of said low and reverse range gear trains to said output shaft (60), whereby said reduction gearing means (5) provide low and Reverse ranges of different directions along a single distinct torque ratio directly interconnecting said intermediate (36) and output (60) shafts.

Claim 7

The transmission of claim 5 wherein: a. said low range gear train comprises an epicyclic gear set including a sun gear (42) driven by said intermediate shaft (36), planetary gears (50) attached to one (56) of said spur gears of said reduction gearing means (5) and a ring gear (52); b. said reverse range gear train comprises an epicyclic gear set including a sun gear (40) driven by said intermediate shaft (36), planetary gears (82) attached to a carrier (84) and a ring gear (52) which is the same ring gear as the ring gear of the epicyclic set of said low range gear train; c. said low range clutch comprises a brake (54) for braking the ring gear (52) of said low range gear train to cause said low range gear train to drive said spur gears (50); and d. said reverse range clutch comprises a brake (68) for braking the carrier (84) of the epicyclic set of said reverse range gear train to cause said ring gear to be driven whereby said ring gear in combination with the sun gear motion will drive the planetary gears of the epicyclic set of said low range gear train and said spur gears in a direction reverse of that in which they are driven by the low range gear train.

Claim 8

An infinitely variable hydromechanical transmission providing three synchronously changeable speed ranges, each with a distinct torque ratio between the output of the hydraulic device and the output shaft, and a reverse range comprising: a. an input means (1); b. an output shaft (60); c. an intermediate shaft (36); d. a variable speed hydromechanical transmission interposed between said input means (1) and said intermediate shaft (36) including: i. a variable speed hydrostatic transmission (2) driven by said input means (1), and ii. a differential gearing means having a first input (32) driven by said hydrostatic transmission, a second input (30) driven by said input means (1) and an output (35) connected to said intermediate shaft (36) whereby said intermediate shaft is driven by the hydromechanical output of said transmission; e. selectable reduction gearing means (5) interconnecting said intermediate shaft (36) and said output shaft (60) including: i. a low range gear train comprising a low range epicyclic gear set including a sun gear (42) driven by said intermediate shaft (36), planetary gears (50), and a ring gear (52), ii. a reverse range gear train comprising a reverse range epicyclic gear set including a sun gear (40) driven by said intermediate shaft (36), planetary gears (82) attached to a carrier (84) and a ring gear (52) which is common with the ring gear (52) of said low range epicyclic set, iii. spur gears (56, 58) driven by said planetary gears (50) of said low range gear train for driving said output shaft (60), iv. a low range clutch (48) comprising a brake (54) for braking the common ring gear (52) of said low and reverse range gear trains to cause the sun gear (42) of said low range set to drive the low range planetary gears (50) and said spur gears (56, 58), v. a reverse range clutch (46) comprising a brake (86) for braking the carrier (84) of said reverse range epicyclic set to drive said common ring gear (52) in combination with the sun gear (42) to cause the low range planetary gears (50) and spur gears (56, 58) to be driven in a direction opposite to that in which they are driven in low range, whereby an actuation of said brakes said intermediate shaft (36) may drive said output shaft (60) in either direction; f. an intermediate and high range gear train (6, 7) comprising: i. a first three-element epicyclic gear set (6) having a sun gear (38) connected to said intermediate shaft (36), planetary gears (62) attached to a carrier (66) and a ring gear (64) carrying a first torque transfer spur gear (67), ii. a second three-element gear set (7) havinG a ring gear (70) carrying a second torque transfer spur gear (71) meshing with said first torque transfer spur gear (67), planetary gears (72) mounted on a carrier (76) connected to said output shaft (60) and a sun gear (74) which is connected to a shaft (75) driven by said input means (1), iii. an intermediate range brake (68) for braking the carrier of said first set to cause said sun gear (38) to drive said ring gear (64), said torque transfer spur gears (67, 71), said second epicyclic set (7) and said output shaft (60) whereby said intermediate shaft (36) may drive said output shaft (60) in an intermediate forward range having a distinct torque ratio different from that of said low range, and iv. a high range clutch mechanism for locking together for common rotation the sun (38) and ring (64) gears of said first set to drive said output shaft (60) in a high forward range having torque distinct from that of the other ranges whereby said transmission operates as controlled by the respective clutch mechanisms in one reverse and three forward ranges wherein each forward range has a distinct torque ratio between the output of said hydrostatic transmission and the output shaft.

Claim 9

An infinitely variable hydromechanical transmission providing three synchronously changeable speed ranges, each with a distinct torque ratio between the output of the hydraulic device and the output shaft, and a reverse range comprising: a. an input means (1); b. an output shaft (60); c. an intermediate shaft (36); d. a variable speed hydromechanical transmission interposed between said input means (1) and said intermediate shaft (36) including: i. a variable speed hydrostatic transmission (2) driven by said input means (1), and ii. a differential gearing means having a first input (32) driven by said hydrostatic transmission, a second input (30) driven by said input means (1) and an output (35) connected to said intermediate shaft (36) whereby said intermediate shaft is driven by the hydromechanical output of said transmission; e. selectable reduction gearing means (5) interconnecting said intermediate shaft (36) and said output shaft (60) including: i. a low range gear train comprising a low range epicyclic gear set including a sun gear (42) driven by said intermediate shaft (36), planetary gears (50), and a ring gear (52), ii. a reverse range gear train comprising a reverse range epicyclic gear set including a sun gear (40) driven by said intermediate shaft (36), planetary gears (82) attached to a carrier (84) and a ring gear (52) which is common with the ring gear (52) of said low range epicyclic set, iii. spur gears (56, 58) driven by said planetary gears (50) of said low range gear train for driving said output shaft (60), iv. a low range clutch (48) comprising a brake (54) for braking the common ring gear (52) of said low and reverse range gear trains to cause the sun gear (42) of said low range set to drive the low range planetary gears (50) and said spur gears (56, 58), v. a reverse range clutch (46) comprising a brake (86) for braking the carrier (84) of said reverse range epicyclic set to drive said common ring gear (52) in combination with the sun gear (42) to cause the low range planetary gears (50) and spur gears (56, 58) to be driven in a direction opposite to that in which they are driven in low range, whereby an actuation of said brakes said intermediate shaft (36) may drive said output shaft (60) in either direction; f. an intermediate and high range gear train (6, 7) comprising: i. a first three-element epicyclic gear set (6) having a sun gear (38) connected to said intermediate shaft (36), planetary gears (62) attached to a carrier (66) and a ring gear (64) carrying a first torque transfer spur gear (67), ii. a second three-element gear set (7) havinG a ring gear (70) carrying a second torque transfer spur gear (71) meshing with said first torque transfer spur gear (67), planetary gears (72) mounted on a carrier (76) connected to said output shaft (60) and a sun gear (74) which is connected to a shaft (75) driven by said input means (1), iii. an intermediate range brake (68) for braking the carrier of said first set to cause said sun gear (38) to drive said ring gear (64), said torque transfer spur gears (67, 71), said second epicyclic set (7) and said output shaft (60) whereby said intermediate shaft (36) may drive said output shaft (60) in an intermediate forward range having a distinct torque ratio different from that of said low range, and iv. a high range clutch mechanism for locking together for common rotation the sun (38) and ring (64) gears of said first set to drive said output shaft (60) in a high forward range having torque distinct from that of the other ranges whereby said transmission operates as controlled by the respective clutch mechanisms in one reverse and three forward ranges wherein each forward range has a distinct torque ratio between the output of said hydrostatic transmission and the output shaft.